SOLUTION: given f(x)=x^3-3x^2-5x+7, find f(-2) thank you

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Question 187449: given f(x)=x^3-3x^2-5x+7, find f(-2)

thank you

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29=x%5E3-3x%5E2-5x%2B7 Start with the given equation.


f%28-2%29=%28-2%29%5E3-3%28-2%29%5E2-5%28-2%29%2B7 Plug in x=-2.


f%28-2%29=1%28-8%29-3%28-2%29%5E2-5%28-2%29%2B7 Cube -2 to get -8.


f%28-2%29=1%28-8%29-3%284%29-5%28-2%29%2B7 Square -2 to get 4.


f%28-2%29=-8-3%284%29-5%28-2%29%2B7 Multiply 1 and -8 to get -8.


f%28-2%29=-8-12-5%28-2%29%2B7 Multiply -3 and 4 to get -12.


f%28-2%29=-8-12%2B10%2B7 Multiply -5 and -2 to get 10.


f%28-2%29=-3 Combine like terms.