The coefficient of $x^{n}$ in the expansion of $(1 - x)^{- 2}$ is.

\frac{2^{n}}{2!}

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n + 1

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n + 2

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2 n

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Solution

The correct option is A $n + 2$
We have, $(1 - x)^{- 2} = 1 + 2 x + 3 x^{2} + . . . + (n + 1) x^{n} + (n + 2) x^{n + 1} + . . .$
$∴$ Coefficient of $x^{n + 1}$ is $n + 2$ .

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