Question B5: Let f(:v) = COS(L' + 2) cos(x 2) and let g(x) = cos(a: + 1) cos(a: 1). (3.) Compute f'(x). (b) Compute g'(:t). (c) Use a calculator to evaluate f' (3) g' (3) and f/ (3.7) g' (3.7). Does this suggest a pattern? ((1) Use appropriate trigonometric identities to show that f'(:c) g'(:t) = 0 for every :3, and conclude that f (1') 9(1):) is constant. Question B6: 2 3x 2 + :L' ' Find all of the critical points and local extreme values of f (at) =