Published by:
CGP EDU Academic Team
Published on: August 14, 2026
The sum of the first n terms of the series 1 2 + 2.2 2 + 3 2 + 2.4 2 + 5 2 + 2.6 2 + . . . is 
, when n is even. When n is odd, the sum is
A
B
C
D
Text Solution
Verified by ExpertsThe correct answer is:
A
If n is odd, n – 1 is even. Sum of (n – 1) terms will be 
.
The nth term will be n 2 . Hence the required sum
= 
+n 2 = 
.
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