To find a maximum or minimum value of a function, look for parts of the expression—
especially squares—that have upper or lower limits.
Undefined
To find values of x for which a function is undefined, look for values that would make a
denominator zero or that would make an expression under a radical negative.
Inverse Functions
To find the inverse of a function:
1. Replace f(x) with y.
2. Solve the equation for x in terms of y.
3. Replace x with f−1(x) and replace y with x.Graphs of inverse functions are symmetric about the line y = x.
The slopes of the lines of inverse functions are reciprocals.