SOLUTION: if f(x) = log5 x+ 4, then f-1(x)=

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Question 31002: if f(x) = log5 x+ 4, then f-1(x)=
Found 2 solutions by acerX, venugopalramana:
Answer by acerX(62) About Me  (Show Source):
You can put this solution on YOUR website!
if I am reading this right:
if f%28x%29+=+log5++x%2B+4, then f-1%28x%29
f(x) is the same as y
if y+=+log5++x%2B+4, then y-1
y-1=log5x%2B4
y=log5x%2B5 or f-1%28x%29=log5x%2B5
please double check the problem and verify it is not asking f(x-1)

Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
if f(x) = log5 x+ 4, then f-1(x)=
LET Y =F(X)=LOG5 (X) +4....TO FIND F^-1(X),WE HAVE TO FIND X IN TERMS OF Y..
LOG5 (X)=Y-4
X =5^(Y-4) = F^-1(X)=5^{F(X)-4}