
Yefim S. answered 01/24/21
Math Tutor with Experience
Because on interval [0, 8] y - x2 is increasing function left sum L4 is lover sum, right sum
R4 is upper sum. Then Δx = (8 - 0)/4 = 2;
L4 = 2(02 + 22 + 42 + 62) = 112; R4 = 2(22 + 42 + 62 + 82) = 240;
T4 = 0.5·2(02 + 82 + 2(22 + 42 + 62)) = 176.
(112 + 240)/2 = 176.
We check that T4 = (L4 + R4)/2