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Write the polynomial of least degree with roots -2, 5, and 7.

User Starlett
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1 Answer

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For roots of -2, 5, and 7.

x = -2, x = 5, and x = 7

x = -2 x = 5 x = 7

(x + 2) = 0 (x - 5) = 0 (x - 7) = 0

The polynomial of least degree would be:
(x -2)(x - 5)(x - 7) = 0

(x -2)(x -5) = x(x - 5) - 2(x -5)

= x² - 5x - 2x + 10

= x² - 7x + 10

(x² - 7x + 10)(x -7)

x(x² - 7x + 10) - 7(x² - 7x + 10)

x³ - 7x² + 10x - 7x² + 49x - 70

x³ - 7x² - 7x² + 10x + 49x - 70

x³ - 14x² + 59x - 70

The least is x³ - 14x² + 59x - 70
User Valeri Voev
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