Mike D. answered 11/23/20
Effective, patient, empathic, math and science tutor
These are left and right Riemann sums
For the first, lower estimate = 2 ( f(2) + f(4) + f(6) + f(8) + f(10)) { as the function is decreasing }
For the upper estimate 2 ( f(0) + f(2) + f(4) + f(6) + f(8))
Then for the 10 rectangles
Lower 1 ( f(1) + f(2) + ... f(10))
Upper 1 ( f(0) + f(1) + ... f(9))
