JEE Main 2021 — Binomial Theorem Question with Solution
From: JEE Main 2021 (Online) 25th July Evening Shift
Question
The sum of all those terms which are rational numbers in the
expansion of (21/3 + 31/4)12 is :
expansion of (21/3 + 31/4)12 is :
Choose an option
Show full solutionCorrect option: D
Correct answer
D43
Step-by-step explanation
Tr + 1 will be rational number when r = 0, 3, 6, 9, 12 & r = 0, 4, 8, 12
r = 0, 12
T1 + T13 = 1 33 + 1 24 1
= 24 + 16 = 43
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