JEE Main 2018MathematicsSequences and SeriesHardMCQ

JEE Main 2018 — Sequences and Series Question with Solution

JEE Main 2018 (16 Apr Online)

Question

The sum of the first 20 terms of the series 1+32+74+158+3116+… is

Choose an option

Show full solutionCorrect option: C
Correct answer
C38+1219

Step-by-step explanation

1+32+74+158+3116+…

=2-1+2-12+2-14+2-18+2-116+…upto 20 terms

=40-1+12+14+18+…upto 20 terms

=40-1-12201-12=40-2+1219=38+1219

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About this question

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.