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numbers and algebraic expressions
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function and its properties
linear function
quadratic function
polynomials
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exponential function
logarithm
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derivative and integral of functions
trigonometry
plane geometry
analytic geometry
solid geometry
combinatorics
probability
elements of statistics
kropki game

The base. Legs. The base angles of an isosceles triangle are equal. The altitude divides the base and the angle at vertex of isosceles triangle into two equal parts. Equal line segments. The altitude of isosceles triangle.