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