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Find the rth term in the expansion of (x+1x)2r

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Question

Find the rth term in the expansion of `(x + 1/x)^(2r)`

Sum
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Solution

We have Tr = `""^(2r)"C"_(r - 1)   (x)^(2r - r + 1) (1/x)^(2r)`.

= `(2r)/((r - 1)(r + 1)) x^(r + 1 - r + 1)`

= `(2r)/((r - 1)(r + 1)) x^2`

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Chapter 8: Binomial Theorem - Solved Examples [Page 132]

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NCERT Exemplar Mathematics Exemplar [English] Class 11
Chapter 8 Binomial Theorem
Solved Examples | Q 1 | Page 132

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