Разложите квадратные трехчлены ** множители x2-2x-15=0

Question

Разложите квадратные трехчлены на множители x2-2x-15=0

Comments

$$ x^2 - 2 x - 15 = (x - 5) (x + 3) $$

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D = (-2)^2 - 4 * 1 * (-15) = 4 + 60 = 64

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x1 = (2 - 8) / 2 = -6 / 2 = -3

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x2 = (2 + 8) / 2 = 10 / 2 = 5

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(x - x1) (x - x2) = (x - (-3)) (x - 5) = (x + 3) (x - 5)

Answer 1

(x - x1) (x - x2) = (x - (-3)) (x - 5) = (x + 3) (x - 5)