JEE Main 2021MathematicsBinomial TheoremProblems Based On Binomial Co Efficient And Collection Of Binomial Co EfficientmediumMCQ

JEE Main 2021 — Binomial Theorem Question with Solution

From: JEE Main 2021 (Online) 18th March Morning Shift

Question

Let (1 + x + 2x2)20 = a0 + a1x + a2x2 + .... + a40x40. Then a1 + a3 + a5 + ..... + a37 is equal to

Choose an option

Show full solutionCorrect option: B
Correct answer
B219(220 21)

Step-by-step explanation



Put x = 1

..... (i)

Put x = 1

..... (ii)

by (i) (ii) we get,



..... (iii)

a39 = coeff. x39 in (1 + x + 2x2)20







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About this question

This is a previous-year question from JEE Main 2021, covering the Binomial Theorem 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.