SOLUTION: g(x)=x=5;h(x)=x-5 , are these functions inverse if so, why?

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Question 74287: g(x)=x=5;h(x)=x-5 , are these functions inverse if so, why?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Functions are "inverse" if one UNDOES what the other DOES.
Mathematically that means: f and g are inverse of one another
if f(g(x))=x and g(f(x))=x
So, let's try it:
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g(x)=x=5;h(x)=x-5 , are these functions inverse if so, why?
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g(f(x))=g(x-5) = (x-5)-5 = x-10
Right away you know they are not inverse because the result was not "x".
If you had tried f(g(x)) first you would have gotten the following:
f(g(x))=f(x-5)=(x-5)-5 = x-10
Again, you did not get "x" as a result and that shows you they are not inverse.
Hope this helps.
Cheers,
Stan H.