JEE Main 2020 — Binomial Theorem Question with Solution
From: JEE Main 2020 (Online) 2nd September Evening Slot
Question
For a positive integer n,
is expanded
in increasing powers of x. If three consecutive
coefficients in this expansion are in the ratio,
2 : 5 : 12, then n is equal to________.
is expanded
in increasing powers of x. If three consecutive
coefficients in this expansion are in the ratio,
2 : 5 : 12, then n is equal to________.
Enter your answer
Show full solutionCorrect answer: 118
Correct answer
118
Step-by-step explanation
Let, three consecutive coefficients are
Now,
...(i)
...(ii)
On solving (i) and (ii) we get n = 118
Now,
...(i)
...(ii)
On solving (i) and (ii) we get n = 118
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