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Expand the expression: (x+1x)6

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Question

Expand the expression: `(x + 1/x)^6`

Sum
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Solution

`(x + 1/x)^6 =  x^6  +  ^6C_1   x^5(1/x) +   ^6C_3  x^3 (1/x)^3  +  ^6C_4   x^2 (1/x)^4  +   ^6C_5  x (1/x)^5  +  (1/x)^6`

= `x^6 + 6. x^5 . 1/x  + 15.  x^4 . 1/x^2  + 20. x^3 . 1/x^3  + 15 . x^2 . 1/x^4  + 6.x  1/(x^5)  + 1/x^6`

= `x^6  + 6x^4  + 15x^2  + 20 + 15/x^2  + 6/x^4  + 1/x^6`

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Chapter 7: Binomial Theorem - EXERCISE 7.1 [Page 133]

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NCERT Mathematics [English] Class 11
Chapter 7 Binomial Theorem
EXERCISE 7.1 | Q 5. | Page 133

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