SOLUTION: f(x)=2x-7 and f^-1(x)= x+7/2, find f(f^-1(x)) if it exists.

Question 173150: f(x)=2x-7 and f^-1(x)= x+7/2, find f(f^-1(x)) if it exists.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
f(x)=2x-7 and f^-1(x)= (x+7)/2, find f(f^-1(x)) if it exists.
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f(f^-1(x)) = f[(x+7)/2] = 2[(x+7)/2]-7 = x+7-7 = x
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Notice how f undoes what f^-1 does.
Similarly f^-1(x) undoes what f does.
That is what "inverse" means.
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Cheers,
Stan H

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