(a) Match the functions x, x, x , x2, x3, x2 with the graphs in the figure below. DEF A 2 B C L x 2 x matches x matches V x matches xz matches x3 matches xz matches (b) What is the relationship between the concavity of y = x2 and y = x2? Between the concavity of y = x3 andy = x3 for x > 0? The concavity of y = x is that of y = x2 . The graph of y = x2 is concave , andy = x2 is concave The concavity of y = x' is that of y = x3 . The graph of y = x3 is concave , and y = x3 is concave