Mark M. answered 01/17/19
Retired math prof. Calc 1, 2 and AP Calculus tutoring experience.
By L4 and R4 I assume that you mean the left and right Riemann Sums with 4 equal subintervals.
If so, then Δx = (8-0)/4 = 2, and f(x) = 2√x.
L4 = f(0)Δx + f(2)Δx + f(4)Δx + f(6)Δx
= 2[2√0 + 2√2 + 2√4 + 2√6]
R4 = 2[2√2 + 2√4 + 2√6 + 2√8]
Evaluate L4 and R4 on your calculator.
Ej N.
where did you get the numbers that replace x for L and R?01/10/23