SOLUTION: Please help me solve this equation: {{{ f(x)=-x^3-x^2+4x+4=0}}}. Find the zeros.

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Please help me solve this equation: {{{ f(x)=-x^3-x^2+4x+4=0}}}. Find the zeros.      Log On


   

Question 318929: Please help me solve this equation: +f%28x%29=-x%5E3-x%5E2%2B4x%2B4=0. Find the zeros.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
graph%28300%2C300%2C-5%2C5%2C-5%2C5%2C+-x%5E3-x%5E2%2B4x%2B4%29
Looks like x=-2, x=-1 and x=2 are zeros.
Verify using the equation.
f%28x%29=+-x%5E3-x%5E2%2B4x%2B4
f%28-2%29=-%28-8%29-%284%29-8%2B4=0
f%28-1%29=-%28-1%29-%281%29-4%2B4=0
f%282%29=-%288%29-%284%29%2B8%2B4=0
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f%28x%29=-%28x%2B2%29%28x-2%29%28x%2B1%29
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x=-2, x=-1 and x=2