SOLUTION: what is f^-1(x) if f(x)=1/2x-3? would the answer be f^-1(x)=1/2x+3? if not what?

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Question 2338: what is f^-1(x) if f(x)=1/2x-3? would the answer be f^-1(x)=1/2x+3? if not what?
Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
ok, inverses of functions...very simple. All you are being asked is basically find the "reverse" function...in "earlier Maths"...what is x equal to, that is all.
so, f(x) = y = 1%2F%282x-3%29
(2x-3)y = 1
2x-3 = 1/y
2x = %281%2Fy%29%2B3
so x = %28%281%2Fy%29%2B3%29%2F2
this is your answer...f%5E-1%28x%29+=+%28%281%2Fx%29%2B3%29%2F2
Note, i have changed the y into an x, because the function asks for f%5E-1%28x%29, not f%5E-1%28y%29.
The acid test is that f(x) and f%5E-1%28x%29 should be opposites of each other,
so put a value in f(x) to give an answer.
then put that answer in f%5E-1%28x%29 to get the original number back as the answer.
eg x=1 into f(x) is -1
so x=-1 into f%5E-1%28x%29 is 1. CORRECT :-)
PS, this working assumes that i have read your f(x) correctly...or is f(x) = %281%2F%282x%29%29-3? If so, you re-do the work to find the inverse :-)
jon.