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numbers and algebraic expressions
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elements of statistics
kropki game
The domain of rational function find search roots (zeros) of a denominator. Examples. y = 5 / x-2, for x = 2 the denominator equal 0. D = R \ 2, all the real numbers except 2. y = 2x+4 / x^2-9, for x = 3 or x = -3 the denominator equal 0. D = R \ {-3,3}, all the real numbers except -3 and 3.