SOLUTION: According it Descartes' Rule of Signs, (a) how many positive real roots does each of the following have? (b) how many negative roots? 17) f (x) = 3x^3 + 9x^2 + 8x (a)_________ (

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Question 92195This question is from textbook
: According it Descartes' Rule of Signs, (a) how many positive real roots does each of the following have? (b) how many negative roots? 17) f (x) = 3x^3 + 9x^2 + 8x (a)_________ (b) __________ This question is from textbook

Answer by uma(370) About Me  (Show Source):
You can put this solution on YOUR website!
f (x) = 3x^3 + 9x^2 + 8x
There are no sign changes in the given expression.
==> there are no positive roots
Consider f(-x) = -3x^3 + 9x^2 - 8x
Here there are 2 sign changes.
==> there are 2 negative roots.
Good Luck!!!