JEE Main 2005 — Binomial Theorem Question with Solution
From: AIEEE 2005
Question
If the coefficient of in equals the coefficient of in , then and satisfy the relation
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
General term of is Tr+1.
Tr+1 =
=
For the coefficient of x7,
22 - 3r = 7
r = 5
So coefficient of x7 = ......(1)
Now General term of is Tr+1.
Tr+1 =
=
For the coefficient of x-7,
11 - 3r = -7
r = 6
Coefficient of x-7 =
According to question,
Coefficient of x7 = Coefficient of x-7
=
Tr+1 =
=
For the coefficient of x7,
22 - 3r = 7
r = 5
So coefficient of x7 = ......(1)
Now General term of is Tr+1.
Tr+1 =
=
For the coefficient of x-7,
11 - 3r = -7
r = 6
Coefficient of x-7 =
According to question,
Coefficient of x7 = Coefficient of x-7
=
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This is a previous-year question from JEE Main 2005, 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.