Find the function’s domain
Compute the first derivative
Set the first derivative equal to zero
Solve for critical points
Find points where the first derivative does not exist
Evaluate the function at all critical points
If the interval is closed, also evaluate the endpoints
Compare all function values
The largest value is the maximum
The smallest value is the minimum
Use the second derivative test if needed
If the second derivative is positive, the point is a local minimum
If the second derivative is negative, the point is a local maximum
If the second derivative is zero, use another test
Check whether the extrema are local or absolute