(14) If f and g are differentiable functions such that f (3) - 5, f'(3) - -8,9(3) = -2 and g'(3) = 7, evaluate each of the following: (a) (4f -13g)'(3) (b) (fg)'(3) ( 0 ) (3 ) ( ) ( 1+9 (3) (15) If f(x) - 3 cos x - 8 sin x, find f'(x) and f" (x). (16) In each case, find the derivative of the given function in simplest form. (a) g(r) - re-"? (b) k(t) = V1 + sin5t. (c) H(v) = In(e2v + v) (17) Find the slope-intercept equation of the line tangent to the graph of y = x2(31 -8x2) 101 at the point (2, -1)