1. Remember! 1 st Derivative test evaluates slope, and is used to determine relative extrema.

2. More examples: Ex 3 p. 183 Find relative extrema of Solution: find 1 st derivative and then critical numbers Critical numbers are

3. So what are the extrema? Check by graphing. Look at technology pitfall on bottom of 183. Intervals (- ∞, -3) (-3, 0) (0, 3) (3, ∞) Test values x = -4 x = -1 x = 1 x = 4 f ‘(x) sign Inc/dec?

4. When using the first derivative test, be sure to consider domain of the original function. Values not in original domain must be looked at too for intervals Ex 4 p. 184 Applying 1 st Derivative test Find relative extrema of Solution: find 1 st derivative and set up intervals using critical numbers and domain problem values

5. So what are the extrema? Check by graphing. Interval (- ∞, -1) (-1, 0) (0, 1) (1, ∞) Test value x = -2 x = -1/2 x = 1/2 x =2 Sign of f’ Inc/Dec?