11-14 Use the Midpoint Rule with the given value of n to approxi- 24. (x3 + 5x ) dx, Rn =- E 6+ mate the integral. Round the answer to four decimal places. 11. feldx , n = 6 12 . [ Vx3 + I dx , n = 5 25-26 Express the integral as a limit of Riemann sums using right endpoints. Do not evaluate the limit. 13. J, x2 4 8 dx, n =5 14. " xsinxax, n =4 25. ( 4 + x2 dx T 15. Use a computer algebra system that evaluates midpoint approximations and graphs the corresponding rectangles (use 26. [ ( x2 + 4 ) dx RiemannSum or middlesum and middlebox commands in Maple) to check the answer to Exercise 13 and illustrate with a graph. Then repeat with n = 10 and n = 20. 27-34 Use the form of the definition of the integral given in Theorem 4 to evaluate the integral. T 16. Use a computer algebra system to compute the left and right Riemann sums for the function f(x) = x/(x + 1) on the 27 . 23x dx 28 . (3 x 2 dx interval [0, 2] with n = 100. Explain why these estimates show that 29 . 3 (5x + 2 ) dx 30 . (* ( 6 - x2) dx dx