Question

The sum of square of  the first n natural numbers is  given by _________

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

(b) n(n-1)/2(2n+1)

(c) n^2(n+1)(2n+1)/6

(d) None of the mentioned

I got this question in examination.

This interesting question is from Special Sequences topic in chapter Basic Structures: Sets, Functions, Sequences, Sums and Matrices of Discrete Mathematics

Answer 1

The correct choice is (a) n(n+1)(2n+1)/6

The explanation: 1^2 + 2^2 + 3^2 + 4^2 +……n^2 = n(1+n)(2n+1)/6.