Question

What does Descartes's Rule of Signs tell you about the real roots of the polynomial?

–2x^3 + 3x^2 – 5x – 2 = 0



There is one positive root and either 2 or 0 negative roots.

There are either 2 or 0 positive roots and there are either 2 or 0 negative roots.

There is one positive root and one negative root.

There are either 2 or 0 positive roots and one negative root.

Answer 1

(2x + 1)(x + 1) = 2x^2 + 3x + 1
(2x^2 + 3x + 1)(x - 2) = 2x^3 -x^2 - 5x - 2)
(2x + 1)(x + 1)(x - 2) = 0
x = 2, -1, -1/2

Answer 2

so is it c ?

Answer 3

Yeah its c

Answer 4

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Answer 5

yeah I'll try