Calculus AB Assignment Concavity 3. Consider the function fx = 2x +3x+6 x+2 A. Find "(x . (Show your work!) B. Graph "(x on your calculator and use this graph to answer the following questions: On what interval(s) is /(x concave up, and how did you use the graph of "(x to estimate this? On what interval(s) is /(x concave down, and how did you use the graph of /"(x to estimate this? Note: You don't need to include a sketch of y = /"(x in your answer. 4. Consider the function /(x _ x2+7x+3 As in the last problem, find "(x (showing all work), and use the graph of this function to estimate where /x is concave up and where /(x is concave down. You don't need to include a sketch of the graph of "(x in your