What formula would be used to calculate the left rectangle

Last updated: 6/15/2023

What formula would be used to calculate the left rectangle approximation of 2x 2 dx using five subintervals O L5 0 4 2 0 2 2 2 0 6 2 2 1 0 2 2 1 4 2 2 1 8 2 O L5 0 4 2 0 0 2 2 0 4 2 2 0 8 2 2 1 2 2 2 1 6 2 O L5 0 4 2 0 4 2 2 0 8 2 2 1 2 2 2 1 6 2 2 2 0 2 O L5 0 2 2 0 2 2 2 0 6 2 2 1 0 2 2 1 4 2 2 1 8 2 A 20 21 22 23 24 25 26 27 28 29