Question

Let $V_r$ denote the sum of the first $r$ terms of an arithmetic progression $(AP)$ whose first term is $r$ and the common difference is $(2r - 1)$ . The sum $V_1 + V_2 + ..... + V_n$ is

• A. $\frac{1}{12} n (n + 1 ) (3n^2 - n + 1)$
• B. $\frac{1}{12} n (n + 1 ) (3n^2 + n + 2)$
• C. $\frac{1}{2} n (2n^2-n-1)$
• D. $\frac{1}{3} (2n^3 - 2n + 3)$

Answer 1

Answer: (B)

$\frac{1}{12} n (n + 1 ) (3n^2 + n + 2)$

Answer 2

Answer (b) $\frac{1}{12} n (n + 1 ) (3n^2 + n + 2)$