i recently for out a problem asking for the riemann sum of sinx from 0<x<3pi/2 using 3 rectangles with right endpoints. I found that the answer was pi/2 and then the exact area of this was 1. am i right in what i did?
The width of your rectangles is , and the heights are , , and . So the Riemann sum should be:
These rectangles are really wide, so you shouldn't expect the result to be close to the actual area, which you have correctly calculated as: