SOLUTION: Find all zeros. One zero has been given F(x)=3x^3+2x^2-12x-8 ;2

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Find all zeros. One zero has been given F(x)=3x^3+2x^2-12x-8 ;2      Log On


   

Question 860137: Find all zeros. One zero has been given
F(x)=3x^3+2x^2-12x-8 ;2
Found 2 solutions by Fombitz, ewatrrr:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
%283x%5E3%2B2x%5E2-12x-8%29%2F%28x-2%29=3x%5E2%2B8x%2B4
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.
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3x%5E2%2B8x%2B4=%283x%2B2%29%28x%2B2%29
So then,
%283x%5E3%2B2x%5E2-12x-8%29=%283x%2B2%29%28x%2B2%29%28x-2%29

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

F(x)=3x^3+2x^2-12x-8  x = 2 one root

Using Synthetic Division to find other 

2	3	2	-12	-8

		6	16	8

	3	8	4	0

F(x)= (x-2)(3x^2 + 8x + 4) = (x-2)(3x+2)(x+2)

All zeros are:  -2, -2/3, 2