JEE Main 2021MathematicsSequences And SeriesSummation Of SeriesmediumMCQ

JEE Main 2021Sequences And Series Question with Solution

From: JEE Main 2021 (Online) 1st September Evening Shift

Question

Let Sn = 1 . (n 1) + 2 . (n 2) + 3 . (n 3) + ..... + (n 1) . 1, n 4.

The sum is equal to :

Choose an option

Show full solutionCorrect option: A
Correct answer
A

Step-by-step explanation

Let Tr = r(n r)

Tr = nr r2







Now,







Option (a)

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About this question

This is a previous-year question from JEE Main 2021, covering the Sequences And Series chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.