I'll need the upper and lower sun for n=3 n=4 and n=6 please

Unless specified, all approximationg rectangles are assumed to have the same width. Evaluate the upper and lower sums for f(x) = 1 + cos -ASXSI, with n = 3, 4, and 6. Illustrate each case with a sketch similar to the figure shown below. (Round your answers to two decimal places.) b X n = 3: upper sum 9.24 X lower sum Illustrate