Posted by Ashley on .
Given f(x)=4+lnx; Find the inverse of f. f^1=?

Algebra 
Reiny,
original:
y = 4 + lnx
inverse:
x = 4 + lny
solving for y
lny = x4
y = e^(x4)
f^1 (x) = e^(x4) 
Algebra 
Kendall,
How do you find the domain and range?

Algebra 
Reiny,
domain is your choice of x's that you can use in your equation
For logs, one of the main properties is that I can only take the log of a positive number
so for y = 4 + lnx , the domain is x > 0
however, the result of taking such logs results in any real number, so the range is y ∈ R
After taking the inverse of a function, the domain of the original becomes the range of the inverse, and the range of the original becomes the domain of the inverse.