Problem 5. (10 points) Suppose the following facts are given: . tan' (x) = sec2 (ac) = 1 + tan?(ac) . If u = tan(?), then sin(x) = 12, cos(x) = 1-u- Use these facts to calculate the integral J - - 1 cos ( x ) da and J 1 sin (x) -2 cos(x) dx. (Hint: use u- substitution.)