In the expansion of {left( {x - frac{1}{x}} r | vedclass

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Question

(a) In the expansion of ${\left( {x - \frac{1}{x}} \right)^6}$,

the general term is $^6{C_r}{x^{6 - r}}{\left( { - \frac{1}{x}} \right)^r}{ = ^6}{C

Vedclass · Accepted Answer

$-20$

Vedclass · Answer

(a) In the expansion of ${\left( {x - \frac{1}{x}} \right)^6}$,

the general term is $^6{C_r}{x^{6 - r}}{\left( { - \frac{1}{x}} \right)^r}{ = ^6}{C_r}{( - 1)^r}{x^{6 - 2r}}$

For term independent of $x,\,\,6 - 2r = 0 $

$\Rightarrow r = 3$

Thus the required coefficient $ = {( - 1)^3}{.^6}{C_3} = - 20$.

In the expansion of ${\left( {x - \frac{1}{x}} \right)^6}$, the constant term is

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