Find a) any critical values and b) any relative extrema.
a) Select the correct choice below and, if necessary, fill in the answer box within your choice.
A. The critical value(s) of the function is/are
(Use a comma to separate answers as needed.)
B. The function has no critical values.
b) Select the correct choice below and, if necessary, fill in the answer box(es) within your choice.
A. The relative maximum point(s) is/are
(Simplify your answer. Type an ordered pair, using integers or fractions. Use a comma to separate answers as needed.)
B. The relative minimum point(s) is/are
(Simplify your answers. Type ordered pairs, using integers or fractions. Use a comma to separate answers as needed.)
C. The relative minimum point(s) is/are
(Simplify your answer. Type an ordered pair, using integers or fractions. Use a comma to separate answers as needed.)
D. There are no relative minimum points and there are no relative maximum points.
Therefore, the answer to part b) is B. The relative minimum point(s) is/are
Step 1 :First, we need to find the derivative of the function
Step 2 :The derivative of
Step 3 :To find the critical points, we set the derivative equal to zero and solve for
Step 4 :Dividing through by 3 gives
Step 5 :Factoring the equation gives
Step 6 :Setting each factor equal to zero gives
Step 7 :Next, we need to determine whether these critical points are relative extrema. We do this by using the second derivative test. The second derivative of a function at a certain point gives the curvature of the function at that point. If the second derivative is positive, the function is concave up and the point is a relative minimum. If the second derivative is negative, the function is concave down and the point is a relative maximum.
Step 8 :The second derivative of
Step 9 :Substituting
Step 10 :Substituting
Step 11 :To find the y-coordinates of these points, we substitute
Step 12 :Substituting
Step 13 :Substituting
Step 14 :Therefore, the answer to part b) is B. The relative minimum point(s) is/are