Published by:
CGP EDU Academic Team
Published on: August 14, 2026
The sum of the following series
+ 
+…. up to 15 terms, is :
Text Solution
Verified by ExpertsThe correct answer is:
D
Sequence series XI T,
Sol. This series can be written as
T r = 
(1 2 + 2 2 + 3 2 + …..r 2 )
T r = 
T r = 
r 2 (r + 1)
sum of n term = 
( Σ r 3 + Σ r 2 )
= 
hence sum of 15 term
= 
= 
[14400 + 1240] = 7820
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