SOLUTION: f(x)=x+2 g(x)=x^2-9 May you help me? I need to find g[f(x)]

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Question 739440: f(x)=x+2
g(x)=x^2-9
May you help me?
I need to find g[f(x)]
Answer by Leaf W.(135) About Me  (Show Source):
You can put this solution on YOUR website!
g[f(x)] means that you need to find g(x) while replacing the "x" with f(x).
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Therefore, if f(x) = x + 2 and g(x) = x%5E2 - 9, then g[f(x)] would be inserting the f(x) expression into g(x) for x => g[f(x)] = %28x+%2B+2%29%5E2+-+9
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FOIL: g[f(x)] = x%5E2+%2B+4x+%2B+4+-+9
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Simplify: g[f(x)] = x%5E2+%2B+4x+-+5
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Therefore, your final answer is g[f(x)] = x%5E2+%2B+4x+-+5. If your teacher wants you to factor, it is g[f(x)] = (x + 5)(x - 1).