SOLUTION: identify all rational zeros for f(x) =x^3+4x^2 -2x+15

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Question 1042709: identify all rational zeros for f(x) =x^3+4x^2 -2x+15
Answer by josgarithmetic(39621) About Me  (Show Source):
You can put this solution on YOUR website!
Rational Roots Theorem tells us here that possible roots to check are plus and minus of 1,3,5,15. Use synthetic division to check each root; remainder of 0 means, root checked is a root of the function.

ONLY ONE rational root, being -5.
The two others are both complex and irrational.
(What are the roots for x%5E2-x%2B3 ?)