The Definite Integral

Question

Given Ln = 3/n n∑i=1[3(3+(i−1)3/n)^4−4(3+(i−1)3/n)^5], express the limit as n→∞ as a definite integral, that is provide a, b and f(x) in the expression ∫ba f(x)dx 

a= Correct, b= Incorrect, f(x)=   

Answer 1

This limit presents such a definite integral: ∫₃⁶1/3(3x⁴ - 4x⁵)dx; so, a = 3; b = 6; f(x) = 1/3(3x⁴ - 4x⁵)