consider the following equation

Consader the equation below. (If an answer does not exist, enter DN ((x) -x3-91-21x+9 (a) Find the interval(s) on which f is increasing. (Enter your answer Find the interval(s) on which fi decreasing. (Enter your answer (b) Find the local minimum and maximum values of f. local minimum value local maximum value (c) Find the inflection point. (x , y ) = Find the interval(s) on which fis concave up. (Enter your answer u Find the interval(s) on which fis concave down. (Enter your