SOLUTION: if f(x)=4-x^2 and g(x)=1-x, find f[g(-2)]

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Question 877608: if f(x)=4-x^2 and g(x)=1-x, find f[g(-2)]
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
g%28x%29+=+1+-+x


g%28-2%29+=+1+-+%28-2%29 Replace x with -2


g%28-2%29+=+1+%2B+2


g%28-2%29+=+3


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f%28x%29+=+4+-+x%5E2


f%28g%28x%29%29+=+4+-+%28g%28x%29%29%5E2 Replace x with g(x)


f%28g%28-2%29%29+=+4+-+%28g%28-2%29%29%5E2 Replace x with -2


f%28g%28-2%29%29+=+4+-+%283%29%5E2 Then plug in g%28-2%29+=+3 (we computed this earlier above).


f%28g%28-2%29%29+=+4+-+9


f%28g%28-2%29%29+=+-5