(a) Find the derivative of f (a) = (a2 + 9 ) (8x -9) by first expanding the polynomials. Enter the fully simplified expression for f () after expanding the polynomials. f (a) = Enter the derivative of f (x). f (2) = (b) Find the derivative of f (a) = (a + 9 ) (8x - 9) by using the product rule. Let g (x) = x + 9 and h (a) = 8x - 9. g (z) = h (a) = f' (2 ) = (c) Are the expressions for the derivative in (a) and (b) the same