Step-by-step explanation:
a = 3, b = 8, and f(x) = √(1 + x).
Δx = (b − a) / n = 5/n
Plugging into the Riemann sum:
∑₁ⁿ f(a + k Δx) · Δx
∑₁ⁿ √(1 + (3 + 5k/n)) · 5/n
∑₁ⁿ √(4 + 5k/n) · 5/n