Let Ln denote the left-endpoint sum using n subintervals and let R, denote the corresponding right-endpoint sum. In the following exercises, compute the indicated left and right sums for the given functions on the indicated interval. 12. L4 for f'(x)= on [2,3] 13. R for g(x) = cos(xx) on [0, 1] In the following exercises, express the limits as integrals. 62. lim sin (2x Ax over [0, 1] n i=1 In the following exercises, evaluate the integral using area formulas. 4-(x-3)dx 78. (3-Lx) (3-LxD)dx 81.