In Section 21.3 we approximated the area under the curve of y = x 2

, from x = 0 to x = 5 by using the function values on the right-hand sides of the approximating rectangles. Calculate two more approximations (as drawn in the figures in Section 21.3), one using the function values on the left-hand sides of the approximating rectangles, and one using the function values in the middle of the approximating rectangles. Use five rectangles in each case.