JEE Main 2018 — Sequences And Series Question with Solution
From: JEE Main 2018 (Online) 16th April Morning Slot
Question
The sum of the first 20 terms of the series
is :
is :
Choose an option
Show full solutionCorrect option: A
Correct answer
A
Step-by-step explanation
1 + + + + + . . . .
= (2 1) + (2 ) + (2 ) + (2 ) + . . . . .+ 20 terms
= (2 + 2 + . . . . . 20 terms) (1 + + + . . . . . 20 terms)
= 2 20
= 40 2 + 2
= 38 +
= (2 1) + (2 ) + (2 ) + (2 ) + . . . . .+ 20 terms
= (2 + 2 + . . . . . 20 terms) (1 + + + . . . . . 20 terms)
= 2 20
= 40 2 + 2
= 38 +
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This is a previous-year question from JEE Main 2018, 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.