Approximating Area with the Midpoint Rule In Exercises 6166, use the Midpoint Rule with n = 4 to approximate the area of the region bounded by the graph of the function and the x-axis over the given interval. 61. x) = x2 + 3, [0, 2] 62. x) = x2 + 4x, [0, 4] 63. x) = tanx, [0,21] 64. x) = cos x, [0,17] 65. x) = In x, [1, 5] 66. x) = xex, [0, 21 . 58. Grand Canyon . . The Grand Canyon is 1800 meters deep at its deepest point. A rock is dropped from the rim above this point. Write the height of the rock as a function of the time t in seconds. How long will it take the rock to hit the canyon floor?4 20. f (x) = x2 + 2 y - (set up definite integral and find exact value of area under the curve)