Question

Let S_n denote the sum of the cubes of the first n natural numbers and s_n denote the sum of the first n natural numbers. Then Σ(for r=1 to n)S_r/s_r equals

(A) (n(n+1)(n+2))/6

(B) (n(n+1))/2

(C) (n² + 3n +2)/2

(D) None of these

Answer 1

Answer is (A)