SOLUTION: How many real and complex roots does the plynomial f(x)=x^3+9x have?

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Question 584915: How many real and complex roots does the plynomial f(x)=x^3+9x have?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=x^3+9x

0=x^3+9x

x^3+9x=0

x(x^2+9)=0

x=0 or x^2+9=0

x=0, x=3i or x=-3i

So there is one real root and two complex roots.
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