Question 94022
f(x)=x^3+5x^2+2x-8 
Is x= -2 a root 
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If -2 is a zero of the function f(-2) will be zero.
Try it:
f(-2) = (-2)^3 + 5(-2)^2 + 3(-2) -8
f(-2) = -8 +5*4 -6 -8
f(-2) = -22 +20
f(-2)  -2
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Since the result is not zero -2 is not a zero.
Cheers
Stan H.