1. Section 1.5 Inverse Functions
domain of f(x) = range of f-1(x)
range of f(x) = domain of f-1(x)
when you compose f(x) and f-1(x) you will get the identity function
f(f-1(x))= f-1(f(x))=x
ex. f(x)=4x, f-1(x) = x/4

2. Steps to find the inverse of a function (rule #13)
1. replace f(x) with y
2. switch x and y
3. solve for y
4. replace y with f-1(x)
ex. f(x) = x+4

3. Verifying Inverse Functions
Which of the functions is the inverse of f(x)= 5/(x-2) ?
g(x) = (x-2)/ h(x) = (5/x) + 2

4. Graphing Inverse Functions
The inverse is a reflection across the y = x line
If (a,b) lies on the graph of the function, then (b,a) lies on the graph of the inverse.
Sketch the graph and its inverse f(x) = 2x-3
A function f has an inverse iff no horizontal line intersects the graph of f at more than one point. This is the horizontal line test.