SOLUTION: If f(g(x)) = 4x^2 - 8x and f(x) = x^2 - 4 , then g(x) = ?

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Question 1076491: If f(g(x)) = 4x^2 - 8x and f(x) = x^2 - 4 , then g(x) = ?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
If f%28g%28x%29%29+=+4x%5E2-8x and f%28x%29+=+x%5E2+-4 , then g%28x%29 = ?
to find g%28x%29;
f%28g%28x%29%29+=+4x%5E2-8x,
from f%28x%29;
%28g%28x%29%29%5E2+-4+=+4x%5E2+-8x
%28g%28x%29%29%5E2+=+4x%5E2+-8x%2B4
%28g%28x%29%29%5E2+=+4%28x%5E2+-2x%2B1%29
%28g%28x%29%29%5E2+=+4%28x-1%29%5E2
g%28x%29+=+highlight%282%28x-1%29%29 or g%28x%29+=+highlight%28-2%28x-1%29%29

check: if f%28x%29+=+x%5E2+-+4 and g%28x%29+=+2%28x-1%29

or