SOLUTION: f(x)=2^x+1, find f^-1(x)

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Question 737828: f(x)=2^x+1, find f^-1(x)
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
The quick easy way is,
y=2%5Ex%2B1
Switch places x and y,
x=2%5Ey%2B1
x-1=2%5Ey
Change to logarithmic form,
log%282%2C%28x-1%29%29=y
f%5E-1%28x%29=log%282%2C%28x-1%29%29