Maths lessons

Theory and problems of mathematics from secondary, high school to first courses of technical careers

  1. (Axiomatic) Definition of probability and its properties

    Difficulty: 8

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  2. A line in the plane: positions regarding a circumference

    Difficulty: 1

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  3. A point in the plane: positions regarding a circumference

    Difficulty: 1

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  4. Absolute deviation and standard deviation

    Difficulty: 6

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  5. Absolute value of a real number

    Difficulty: 6

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  6. Absolute, relative, cumulative frequency and statistical tables

    Difficulty: 3

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  7. Adding and subtracting polynomials

    Difficulty: 4

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  8. Algebraic structure for addition and multiplication of rational numbers

    Difficulty: 6

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  9. Almost direct integrals

    Difficulty: 6

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  10. Amplification and simplification radicals

    Difficulty: 4

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  11. An introduction to exponential equation

    Difficulty: 6

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  12. Angle between two planes and between a straight line and a plane

    Difficulty: 7

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  13. Angle between two straight lines

    Difficulty: 7

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  14. Angles between straight lines

    Difficulty: 7

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  15. Angles in radians

    Difficulty: 6

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  16. Angles: type of angles, measure and operations

    Difficulty: 2

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  17. Applications of the scalar product

    Difficulty: 7

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  18. Arbitrary union and intersection

    Difficulty: 8

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  19. Area and perimeter of a circumference

    Difficulty: 2

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  20. Areas delimited by two functions

    Difficulty: 8

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  21. Areas of enclosures in the plane

    Difficulty: 9

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  22. Arithmetical mean

    Difficulty: 1

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  23. Arithmetical progression: definition

    Difficulty: 6

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  24. Arrangement of the real numbers

    Difficulty: 5

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  25. Asymptotes of a function

    Difficulty: 8

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  26. Average, variance and standard deviation

    Difficulty: 7

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  27. Axial and central symmetry

    Difficulty: 9

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  28. Bars diagram and Polygon of frequencies

    Difficulty: 1

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  29. Base change of the logarithms

    Difficulty: 7

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  30. Basis and coordinates

    Difficulty: 7

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  31. Bayes's theorem

    Difficulty: 7

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  32. Biquadratic equations

    Difficulty: 5

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  33. Bounded functions

    Difficulty: 6

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  34. Bounded sequences

    Difficulty: 6

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  35. Boxes method

    Difficulty: 1

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  36. Caesar's method

    Difficulty: 1

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  37. Calculation of apothems and edges of a pyramid

    Difficulty: 5

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  38. Calculation of function limits

    Difficulty: 7

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  39. Calculation of surface areas in space

    Difficulty: 10

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  40. Calculation of volumes by direct integration

    Difficulty: 9

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  41. Calculations of areas in the plane using Green's theorem

    Difficulty: 10

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  42. Cartesian axes and representation of points in the plane

    Difficulty: 1

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  43. Changes of variables in double integrals

    Difficulty: 10

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  44. Circumference that goes through 3 given points

    Difficulty: 6

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  45. Classification and properties of the triangles

    Difficulty: 2

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  46. Classification of the pyramids

    Difficulty: 5

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  47. Combinations with repetition

    Difficulty: 6

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  48. Combinations without repetition

    Difficulty: 6

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  49. Combinatorial numbers

    Difficulty: 5

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  50. Combined operations

    Difficulty: 1

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  51. Compatible and incompatible events

    Difficulty: 5

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  52. Complement of a set

    Difficulty: 4

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  53. Complex and simple measurements

    Difficulty: 2

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  54. Complex measurement and simple measurement

    Difficulty: 3

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  55. Complex numbers from polar to binomic form

    Difficulty: 7

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  56. Complex numbers in the polar form: module and argument

    Difficulty: 7

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  57. Complex numbers in trigonometric form: product and quotient

    Difficulty: 9

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  58. Compound interest

    Difficulty: 6

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  59. Compound rule of three

    Difficulty: 3

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  60. Computation of images and inverse images

    Difficulty: 4

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  61. Computing first-order and second-order determinants

    Difficulty: 5

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  62. Concavity and convexity

    Difficulty: 7

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  63. Concavity and convexity, inflection points of a function

    Difficulty: 8

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  64. Concept and equation of a function

    Difficulty: 3

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  65. Concept and expression of a real function

    Difficulty: 6

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  66. Conditional probability

    Difficulty: 6

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  67. Cones

    Difficulty: 4

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  68. Constant function, Linear function and Affine function

    Difficulty: 6

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  69. Contingency table

    Difficulty: 6

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  70. Continuity in a closed interval and theorem of Weierstrass

    Difficulty: 8

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  71. Continuity of a function at a point

    Difficulty: 7

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  72. Continuous equation of a straight line in the space

    Difficulty: 7

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  73. Continuous equation of the straight line

    Difficulty: 5

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  74. Continuous functions

    Difficulty: 7

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  75. Conversion from decimal base into another system of numeration

    Difficulty: 8

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  76. Converting sums into products and products into sums

    Difficulty: 6

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  77. Coordinates of a point, components of a vector and midpoint of a segment

    Difficulty: 6

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  78. Cramer's rule

    Difficulty: 7

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  79. Cube

    Difficulty: 4

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  80. Cylinders

    Difficulty: 4

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  81. Decimal expression of rational numbers

    Difficulty: 4

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  82. Decimal metric system: length, mass, capacity, surface and volume

    Difficulty: 1

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  83. Defined areas under a function

    Difficulty: 7

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  84. Definite integral and Barrow's rule

    Difficulty: 7

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  85. Definition and basic elements of a circumference

    Difficulty: 1

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  86. Definition and classification of polynomials

    Difficulty: 3

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  87. Definition and elements of the parabola

    Difficulty: 6

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  88. Definition and general solving of quadratic equations

    Difficulty: 4

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  89. Definition and general term of a sequence

    Difficulty: 6

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  90. Definition and how to solve linear equations

    Difficulty: 2

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  91. Definition and notation of sets

    Difficulty: 3

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  92. Definition and real straight line

    Difficulty: 5

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  93. Definition of a square root

    Difficulty: 4

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  94. Definition of an angle and noteworthy angles

    Difficulty: 1

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  95. Definition of complex numbers

    Difficulty: 7

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  96. Definition of decimal numbers

    Difficulty: 1

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  97. Definition of indeterminate form

    Difficulty: 8

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  98. Definition of irrational numbers

    Difficulty: 4

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  99. Definition of probability, sample space and sure and impossible event

    Difficulty: 4

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  100. Definition of rational numbers

    Difficulty: 4

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  101. Definition, analytical expression and properties of scalar product

    Difficulty: 7

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  102. Definition, basic elements and types of centers of the triangle

    Difficulty: 2

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  103. Definitions, matrix and main matrix of the conics

    Difficulty: 9

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  104. Definiton and associated matrixes of analytical quadric

    Difficulty: 9

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  105. Dependent and independent events

    Difficulty: 6

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  106. Derivative at a point

    Difficulty: 6

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  107. Derivative of a constant function

    Difficulty: 6

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  108. Derivative of a power

    Difficulty: 6

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  109. Derivative of exponential, logarithmic and a pow x function

    Difficulty: 6

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  110. Derivative of the composition of functions (chain rule)

    Difficulty: 7

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  111. Derivative of the division of two functions

    Difficulty: 6

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  112. Derivative of the linear function

    Difficulty: 6

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  113. Derivative of the product of two functions

    Difficulty: 6

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  114. Derivative of the sum of two functions

    Difficulty: 6

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  115. Derivative of trigonometric functions

    Difficulty: 6

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  116. Detection of elementary functions

    Difficulty: 7

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  117. Diagram of sectors

    Difficulty: 2

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  118. Differentiability and its relation with continuity

    Difficulty: 6

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  119. Direct and inverse proportion

    Difficulty: 2

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  120. Direct integrals for the polynomials

    Difficulty: 6

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  121. Discontinuity of functions: Avoidable, Jump and Essential discontinuity

    Difficulty: 8

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  122. Discriminant of a quadratic equation

    Difficulty: 6

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  123. Distance between a point and a straight line

    Difficulty: 7

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  124. Distance between a straight line and a plane in space

    Difficulty: 7

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  125. Distance between two planes in space

    Difficulty: 7

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  126. Distance between two points

    Difficulty: 5

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  127. Distance between two points in space

    Difficulty: 7

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  128. Distance between two straight lines

    Difficulty: 7

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  129. Distance between two straight lines in space

    Difficulty: 7

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  130. Distance from a point to a plane in space

    Difficulty: 7

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  131. Distance from a point to a straight line in space

    Difficulty: 7

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  132. Dividing fractions

    Difficulty: 2

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  133. Divisibility criteria

    Difficulty: 2

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  134. Divisors and multiples of a number

    Difficulty: 1

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  135. Dodecahedron

    Difficulty: 5

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  136. Domain of a function

    Difficulty: 6

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  137. Elements of a polygon and classification

    Difficulty: 1

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  138. Elements of a square root and calculation step by step

    Difficulty: 4

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  139. Equality between sets. Subsets and Supersets

    Difficulty: 4

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  140. Equation of the circumference I: reduced equation

    Difficulty: 6

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  141. Equation of the circumference II: general equation

    Difficulty: 6

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  142. Equation of the ellipse with center (x0, y0) and focal axis parallel to x axis

    Difficulty: 7

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  143. Equation of the ellipse with center (x0, y0) and focal axis parallel to y axis

    Difficulty: 7

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  144. Equation of the ellipse with foci on the axis OX

    Difficulty: 6

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  145. Equation of the ellipse with foci on the axis OY

    Difficulty: 6

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  146. Equation of the horizontal hyperbolas

    Difficulty: 7

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  147. Equation of the horizontal parabola with generic vertex

    Difficulty: 7

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  148. Equation of the vertical hyperbolas

    Difficulty: 7

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  149. Equation of the vertical parabola with generic vertex

    Difficulty: 7

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  150. Equation slope-point of the straight line

    Difficulty: 5

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  151. Equations with factorial numbers and combinatorial numbers

    Difficulty: 7

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  152. Equilateral hyperbola

    Difficulty: 7

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  153. Equivalent fractions

    Difficulty: 7

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  154. Equivalent fractions: simplification and irreducible fraction

    Difficulty: 2

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  155. Equivalent linear equations

    Difficulty: 2

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  156. Equivalent systems

    Difficulty: 8

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  157. Euclidean invariants of the conics

    Difficulty: 9

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  158. Euclidian distance

    Difficulty: 9

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  159. Even and odd functions

    Difficulty: 6

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  160. Exact ordinary differential equations

    Difficulty: 9

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  161. Explicit equation of the straight line

    Difficulty: 5

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  162. Exponential functions

    Difficulty: 7

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  163. Exponentiation and roots of complex numbers in trigonometric form (Moivre's formula)

    Difficulty: 9

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  164. Exponentiation of the imaginary unit

    Difficulty: 7

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  165. Express and operate with time in hours, minutes and seconds

    Difficulty: 2

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  166. Extracting common factor

    Difficulty: 2

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  167. Extrema: maximum and minimum

    Difficulty: 6

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  168. Factorial and combinatorial numbers

    Difficulty: 5

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  169. Factorization

    Difficulty: 1

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  170. Factorization of radicals

    Difficulty: 5

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  171. Finite and infinite limits

    Difficulty: 8

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  172. First degree inequations

    Difficulty: 4

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  173. Formalization of rational numbers

    Difficulty: 9

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  174. Fraction as a percentage

    Difficulty: 2

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  175. From decimal numbers to fractions

    Difficulty: 2

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  176. Fubini's theorem

    Difficulty: 9

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  177. Function composition

    Difficulty: 7

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  178. Functions defined by parts

    Difficulty: 8

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  179. Functions: Graphic representation

    Difficulty: 3

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  180. Fundamental concepts of vectors

    Difficulty: 5

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  181. Fundamental trigonometric relations

    Difficulty: 6

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  182. Gaussian elimination method

    Difficulty: 8

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  183. General equation (or Cartesian or implicit) of the straight line

    Difficulty: 5

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  184. General equation of a plane

    Difficulty: 7

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  185. General method for the calculation of determinants

    Difficulty: 7

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  186. General term of a geometric progression

    Difficulty: 6

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  187. General term of an arithmetical progression

    Difficulty: 6

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  188. Geometric interpretation of the derivative

    Difficulty: 6

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  189. Geometric interpretation of the scalar product

    Difficulty: 7

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  190. Geometric mean

    Difficulty: 5

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  191. Geometric progression: definition

    Difficulty: 6

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  192. Geometric transformation classification scheme

    Difficulty: 9

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  193. Geometric transformations

    Difficulty: 9

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  194. Gradient of a scalar field, divergence and rotational of a vector field

    Difficulty: 9

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  195. Graph of a function

    Difficulty: 4

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  196. Graphic determination of the domain and of the image

    Difficulty: 4

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  197. Graphic representation of a function

    Difficulty: 7

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  198. Greatest common divisor and Least common multiple

    Difficulty: 1

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  199. Heron's formula for the area of a triangle

    Difficulty: 3

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  200. Histogram

    Difficulty: 2

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  201. Homogeneous linear equations of order 2 with non constant coefficients

    Difficulty: 10

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  202. Homogeneous linear equations of order n with constant coefficients

    Difficulty: 10

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  203. Icosahedron

    Difficulty: 5

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  204. Icosahedron: Surface area and volume

    Difficulty: 4

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  205. Identity of symmetry

    Difficulty: 5

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  206. Image of a function

    Difficulty: 6

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  207. Implicit equations of a straight line in the space

    Difficulty: 7

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  208. Improper integrals

    Difficulty: 8

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  209. Incomplete quadratic equations

    Difficulty: 6

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  210. Increasing and decreasing functions

    Difficulty: 7

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  211. Increasing and decreasing functions, maximums and minimums of a function

    Difficulty: 8

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  212. Increasing and decreasing intervals

    Difficulty: 7

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  213. Indefinite integral

    Difficulty: 6

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  214. Independent event

    Difficulty: 6

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  215. Indeterminate form 0 x infinity

    Difficulty: 8

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  216. Indeterminate form 0/0

    Difficulty: 8

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  217. Indeterminate form 1 raised to infinity

    Difficulty: 8

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  218. Indeterminate form infinity minus infinity

    Difficulty: 8

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  219. Indeterminate form infinity/infinity

    Difficulty: 8

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  220. Inequations with two variables

    Difficulty: 6

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  221. Infinite sums of series

    Difficulty: 6

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  222. Infinity's comparison

    Difficulty: 8

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  223. Injective, exhaustive and bijective functions

    Difficulty: 6

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  224. Integral along a curve

    Difficulty: 10

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  225. Integral on a surface

    Difficulty: 10

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  226. Integrals in the regions of space and in dimension n

    Difficulty: 10

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  227. Integrals of functions defined by parts

    Difficulty: 8

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  228. Integrals of simple fractions

    Difficulty: 7

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  229. Integrals with changes of variable

    Difficulty: 7

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  230. Integration by parts

    Difficulty: 7

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  231. Interpolation of Hermite

    Difficulty: 9

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  232. Intersection of a circumference and a straight line

    Difficulty: 6

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  233. Intervals

    Difficulty: 6

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  234. Introduction and properties of inequations

    Difficulty: 4

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  235. Introduction to fractions

    Difficulty: 1

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  236. Introduction to intervals

    Difficulty: 4

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  237. Invariants of the quadrics and Euclidean classification

    Difficulty: 9

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  238. Inverse interpolation

    Difficulty: 9

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  239. Inverse matrix using determinants

    Difficulty: 8

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  240. Inverse matrix: method of Gaussian elimination

    Difficulty: 8

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  241. Inverse trigonometric ratios: cosecant, secant and cotangent

    Difficulty: 4

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  242. Irrational functions

    Difficulty: 7

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  243. Lagrange's method

    Difficulty: 9

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  244. Laplace's rule

    Difficulty: 4

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  245. Law of sines and cosines

    Difficulty: 7

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  246. Law of total probability

    Difficulty: 7

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  247. Limit of a function in a point

    Difficulty: 6

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  248. Limit of the sequence

    Difficulty: 8

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  249. Limited and canonical equations of the quadrics

    Difficulty: 9

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  250. Limits in the infinite

    Difficulty: 7

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  251. Linear Combination of vectors

    Difficulty: 7

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  252. Linear diophantine equation

    Difficulty: 8

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  253. Linear equation with n unknowns

    Difficulty: 5

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  254. Linear equations of order n with constant coefficients

    Difficulty: 10

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  255. Linear inequations of two variables

    Difficulty: 6

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  256. Linear ordinary differential equations

    Difficulty: 9

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  257. Linear systems of three equations with three unknowns

    Difficulty: 6

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  258. Linearly dependent and linearly independent vectors

    Difficulty: 7

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  259. Logarithmic equations of first degree

    Difficulty: 6

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  260. Logarithmic equations of second degree

    Difficulty: 7

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  261. Logarithmic functions

    Difficulty: 7

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  262. Logarithmic, exponential and trigonometric direct integrals

    Difficulty: 6

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  263. Logarithms: definition and properties

    Difficulty: 7

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  264. M x n linear systems of equations

    Difficulty: 8

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  265. Mathematical expectation

    Difficulty: 9

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  266. Matrix concept and types of matrices

    Difficulty: 4

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  267. Maximization and minimization

    Difficulty: 7

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  268. Maximun, minimum and inflection points of a function

    Difficulty: 7

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  269. Measurement of angles in degrees, minutes and seconds

    Difficulty: 3

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  270. Method of equalization

    Difficulty: 5

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  271. Mixed numbers

    Difficulty: 2

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  272. Monomials

    Difficulty: 2

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  273. Monotonicity: increasing and decreasing functions

    Difficulty: 6

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  274. Monotonous sequences

    Difficulty: 6

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  275. Multiplication and division of decimal numbers

    Difficulty: 2

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  276. Multiplication of fractions

    Difficulty: 2

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  277. Newton's binomial and Pascal's triangle

    Difficulty: 6

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  278. Newton's method

    Difficulty: 9

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  279. Non homogeneous systems of linear ODE with constant coefficients

    Difficulty: 10

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  280. Non rectangular regions of integration

    Difficulty: 9

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  281. Normal straight line to a curve at a point

    Difficulty: 7

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  282. Notable products

    Difficulty: 3

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  283. Notation, complementary minors and adjoint matrix

    Difficulty: 5

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  284. ODE's homogeneous systems with constant coefficients

    Difficulty: 10

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  285. Octahedron

    Difficulty: 5

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  286. Operations among events: union, intersection, difference and complement

    Difficulty: 5

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  287. Operations and limits with sequences

    Difficulty: 8

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  288. Operations with algebraic fractions

    Difficulty: 7

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  289. Operations with complex numbers in binomic form

    Difficulty: 7

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  290. Operations with complex numbers in polar form

    Difficulty: 7

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  291. Operations with integers

    Difficulty: 1

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  292. Operations with monomials

    Difficulty: 2

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  293. Operations with powers

    Difficulty: 1

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  294. Operations: Sum and product of real numbers

    Difficulty: 5

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  295. Optimitzation

    Difficulty: 7

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  296. Order relation: inclusion of intervals

    Difficulty: 6

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  297. Ordinary differential equation (ODE)

    Difficulty: 9

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  298. Orthogonal basis and orthonormal basis

    Difficulty: 7

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  299. Parametric equations of a plane

    Difficulty: 7

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  300. Parametric equations of a straight line in the space

    Difficulty: 7

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  301. Parametrical equations of the straight line

    Difficulty: 5

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  302. Parametrization of curves

    Difficulty: 10

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  303. Parametrization of surfaces

    Difficulty: 10

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  304. Partial derivatives

    Difficulty: 9

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  305. Percentages

    Difficulty: 2

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  306. Perimeter and area of a triangle

    Difficulty: 1

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  307. Periodic functions

    Difficulty: 6

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  308. Permutations with repetition

    Difficulty: 6

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  309. Permutations without repetition

    Difficulty: 6

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  310. Perpendicular straight lines

    Difficulty: 6

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  311. Perpendicular straight lines in space

    Difficulty: 7

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  312. Perpendicularity between straight line and plane

    Difficulty: 7

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  313. Phantom sums

    Difficulty: 1

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  314. Physical interpretation of the derivative

    Difficulty: 6

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  315. Polyhedrons: basic definitions and classification

    Difficulty: 4

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  316. Polynomial functions: constant, affine and quadratic

    Difficulty: 5

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  317. Polynomial interpolation: definition

    Difficulty: 9

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  318. Powers

    Difficulty: 1

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  319. Powers of fractional exponent

    Difficulty: 4

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  320. Powers with negative bases

    Difficulty: 3

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  321. Prime and composite numbers

    Difficulty: 1

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  322. Prisms

    Difficulty: 4

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  323. Probability of the union and the intersection of events

    Difficulty: 6

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  324. Problems with clocks

    Difficulty: 4

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  325. Problems with linear equations

    Difficulty: 3

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  326. Problems with polynomials and algebraic fractions

    Difficulty: 7

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  327. Product of a real number by a vector

    Difficulty: 6

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  328. Product of matrices

    Difficulty: 5

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  329. Product of n terms of a geometric progression

    Difficulty: 6

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  330. Product of polynomials

    Difficulty: 4

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  331. Product, division and sum of square roots

    Difficulty: 4

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  332. Proper and improper fractions

    Difficulty: 1

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  333. Properties of determinants

    Difficulty: 7

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  334. Properties of sets

    Difficulty: 5

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  335. Properties of the operations with intervals

    Difficulty: 7

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  336. Properties of the product and the quotient of the logarithms

    Difficulty: 7

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  337. Property of Darboux (theorem of the intermediate value)

    Difficulty: 8

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  338. Proportional distributions: direct and inverse

    Difficulty: 5

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  339. Pyramid and truncated Pyramid

    Difficulty: 4

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  340. Pythagorean theorem

    Difficulty: 3

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  341. Quadratic diophantine equations

    Difficulty: 8

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  342. Quadratic equation given its solutions or the sum and product of roots

    Difficulty: 6

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  343. Quadratic inequations

    Difficulty: 6

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  344. Quotient of polynomials

    Difficulty: 4

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  345. Radicals reduction to common index

    Difficulty: 5

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  346. Random variables

    Difficulty: 6

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  347. Range

    Difficulty: 3

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  348. Rank of a matrix by means of determinants

    Difficulty: 7

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  349. Rank of a matrix: Gaussian method

    Difficulty: 7

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  350. Rational functions

    Difficulty: 7

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  351. Rationalization of radicals

    Difficulty: 5

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  352. Reduced and canonical equations of the conics

    Difficulty: 9

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  353. Reduced equation of the horizontal hyperbola

    Difficulty: 6

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  354. Reduced equation of the horizontal parabola

    Difficulty: 6

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  355. Reduced equation of the vertical hyperbola

    Difficulty: 6

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  356. Reduced equation of the vertical parabola

    Difficulty: 6

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  357. Reduction of algebraic fractions to a common denominator

    Difficulty: 7

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  358. Reduction or elimination method

    Difficulty: 5

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  359. Regular dodecahedron: Surface area and volume

    Difficulty: 4

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  360. Regular octahedron: Surface area and volume

    Difficulty: 4

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  361. Relative position of three planes

    Difficulty: 7

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  362. Relative position of two planes

    Difficulty: 7

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  363. Relative position of two straight lines

    Difficulty: 7

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  364. Relative positions between straight lines

    Difficulty: 5

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  365. Relative positions of a straight line and a plane

    Difficulty: 7

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  366. Relative positions of two circumferences in the plane

    Difficulty: 1

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  367. Remainder theorem and Factor theorem

    Difficulty: 5

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  368. Representation of complex numbers in polar form

    Difficulty: 7

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  369. Representation of complex numbers in the plane

    Difficulty: 7

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  370. Right triangle resolution using trigonometric identities

    Difficulty: 5

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  371. Root and factorization of a polynomial

    Difficulty: 5

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  372. Rotations

    Difficulty: 9

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  373. Rouché–Capelli theorem

    Difficulty: 7

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  374. Rounding and truncating decimal numbers

    Difficulty: 1

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  375. Ruffini's rule

    Difficulty: 5

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  376. Sarrus' rule: Computing third-order determinants

    Difficulty: 6

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  377. Saxon measurements

    Difficulty: 2

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  378. Scalar field and vector field

    Difficulty: 9

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  379. Separable ordinary differential equations

    Difficulty: 9

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  380. Set of numbers (Real, integer, rational, natural and irrational numbers)

    Difficulty: 6

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  381. Set product

    Difficulty: 4

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  382. Sets cardinality

    Difficulty: 3

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  383. Sets differences

    Difficulty: 1

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  384. Side continuity

    Difficulty: 7

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  385. Side limits

    Difficulty: 6

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  386. Similarities among figures: triangles

    Difficulty: 2

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  387. Similarities among polygons

    Difficulty: 4

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  388. Simple interest

    Difficulty: 6

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  389. Simplification and expansion of algebraic fractions

    Difficulty: 7

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  390. Simplification in expressions with factorials

    Difficulty: 5

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  391. Situation of the irrational numbers on the straight line

    Difficulty: 5

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  392. Solution of triangles

    Difficulty: 7

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  393. Solving an exponential equation applying properties of the power

    Difficulty: 7

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  394. Solving an exponential equation by logarithmization

    Difficulty: 7

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  395. Solving an exponential equation by reducing to an equal base

    Difficulty: 7

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  396. Solving an exponential equation by variable change

    Difficulty: 7

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  397. Solving trigonometric equations

    Difficulty: 7

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  398. Sorting fractions

    Difficulty: 1

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  399. Spheres and theirs geometric figures

    Difficulty: 5

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  400. Square root of decimal numbers

    Difficulty: 2

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  401. Statistical basic concepts

    Difficulty: 1

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  402. Statistical variables

    Difficulty: 1

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  403. Stifel formula

    Difficulty: 6

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  404. Study of the ellipse

    Difficulty: 6

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  405. Study of the hyperbola

    Difficulty: 6

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  406. Substitution method

    Difficulty: 5

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  407. Subtraction of natural numbers and its properties

    Difficulty: 1

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  408. Sum and subtract of vectors

    Difficulty: 6

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  409. Sum and subtraction of fractions

    Difficulty: 2

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  410. Sum of matrices

    Difficulty: 4

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  411. Sum of natural numbers and its properties

    Difficulty: 1

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  412. Sum of terms of an arithmetical progression

    Difficulty: 6

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  413. Sum of the terms of a geometric progression

    Difficulty: 6

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  414. Sum, difference, product and division

    Difficulty: 6

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  415. Symmetry, periodicity and intersection points of a function

    Difficulty: 7

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  416. System of decimal, binary and hexadecimal numeration

    Difficulty: 8

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  417. System of reference

    Difficulty: 7

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  418. Systems in echelon form

    Difficulty: 8

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  419. Systems of inequations with one variable

    Difficulty: 5

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  420. Systems of inequations with two variables

    Difficulty: 7

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  421. Systems of logarithmic equations

    Difficulty: 7

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  422. Systems of non-linear equations

    Difficulty: 6

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  423. Table for direct integrals

    Difficulty: 6

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  424. Tales'theorem

    Difficulty: 3

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  425. Tangent straight line to a curve at a point

    Difficulty: 7

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  426. Taylor's polynomial

    Difficulty: 9

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  427. Tetrahedron

    Difficulty: 4

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  428. Tetrahedron: Surface area and volume

    Difficulty: 3

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  429. The Derivative function

    Difficulty: 6

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  430. The Euclides algorithm

    Difficulty: 8

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  431. The absolute value function

    Difficulty: 8

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  432. The annulus

    Difficulty: 3

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  433. The average change

    Difficulty: 6

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  434. The binomial (or Bernoulli) distribution

    Difficulty: 8

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  435. The circle

    Difficulty: 2

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  436. The cone: Surface area and volume

    Difficulty: 4

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  437. The cube: Surface area and volume

    Difficulty: 3

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  438. The cylinder: Surface area and volume

    Difficulty: 4

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  439. The distribution function

    Difficulty: 7

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  440. The factorial of a number

    Difficulty: 5

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  441. The frustum of cone: Surface area and volume

    Difficulty: 4

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  442. The frustum of pyramid: Surface area and volume

    Difficulty: 4

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  443. The lune

    Difficulty: 3

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  444. The median

    Difficulty: 2

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  445. The mode

    Difficulty: 1

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  446. The normal (or Gaussian) distribution

    Difficulty: 8

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  447. The order of decimal numbers

    Difficulty: 1

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  448. The orthohedron: Surface area and volume

    Difficulty: 4

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  449. The principle of addition and multplication

    Difficulty: 6

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  450. The prism: Surface area and volume

    Difficulty: 4

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  451. The probability function

    Difficulty: 6

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  452. The pyramid: Surface area and volume

    Difficulty: 4

    View subject

  453. The rectangle

    Difficulty: 1

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  454. The regular polygon

    Difficulty: 2

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  455. The rhomboid

    Difficulty: 2

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  456. The rhombus

    Difficulty: 2

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  457. The set of the integers

    Difficulty: 1

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  458. The set of the natural numbers, order and representation

    Difficulty: 1

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  459. The sexagesimal system and its operations

    Difficulty: 3

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  460. The sphere: Surface area and volume

    Difficulty: 4

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  461. The spherical area: Surface area and volume

    Difficulty: 5

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  462. The spherical dome: Surface area and volume

    Difficulty: 5

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  463. The spindle and the wedge: Surface area and volume

    Difficulty: 5

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  464. The square

    Difficulty: 1

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  465. The sum and subtraction of decimal numbers

    Difficulty: 2

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  466. The trapezoid

    Difficulty: 2

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  467. The triangle

    Difficulty: 1

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  468. Theorem of Bolzano

    Difficulty: 8

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  469. Theorem of Green, theorem of Gauss and theorem of Stokes

    Difficulty: 10

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  470. Traditional measurements

    Difficulty: 2

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  471. Transformation of ODE of order n

    Difficulty: 9

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  472. Translations

    Difficulty: 9

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  473. Transposed matrix

    Difficulty: 4

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  474. Tree diagrams

    Difficulty: 5

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  475. Triangular systems of differential equations

    Difficulty: 10

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  476. Trigonometric Ratios of 30º, 45º, 90º

    Difficulty: 4

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  477. Trigonometric Ratios: sine, cosine and tangent

    Difficulty: 4

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  478. Trigonometric functions

    Difficulty: 6

    View subject

  479. Trigonometric functions: characteristics of sine, cosine and tangent

    Difficulty: 7

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  480. Trigonometric identities in one angle

    Difficulty: 6

    View subject

  481. Trigonometric identities of other angles

    Difficulty: 6

    View subject

  482. Trigonometric identities: half an angle, double an angle, sum and difference of two angles

    Difficulty: 6

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  483. Trigonometric ratios

    Difficulty: 7

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  484. Trigonometric ratios in the circumference

    Difficulty: 4

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  485. Types of decimal numbers

    Difficulty: 2

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  486. Types of polygons

    Difficulty: 1

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  487. Unicity of norms

    Difficulty: 10

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  488. Union and intersection of sets

    Difficulty: 4

    View subject

  489. Union, intersection and complementary of intervals

    Difficulty: 7

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  490. Using logarithms to simplify expressions

    Difficulty: 7

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  491. Validity area of several simultaneos linear inequations

    Difficulty: 7

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  492. Variance and Standard deviation

    Difficulty: 6

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  493. Variations with repetition

    Difficulty: 6

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  494. Variations without repetition

    Difficulty: 6

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  495. Vector equation of a plane

    Difficulty: 7

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  496. Vector equation of a straight line in the space

    Difficulty: 7

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  497. Vector equation of the straight line

    Difficulty: 5

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  498. Vector product

    Difficulty: 8

    View subject

  499. Volumes calculation using Gauss' theorem

    Difficulty: 10

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  500. n-th roots

    Difficulty: 7

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  501. p-adic distance

    Difficulty: 10

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