# ISI2015-DCG-21

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The value of the term independent of $x$ in the expansion of $(1-x)^2(x+\frac{1}{x})^7$ is

1. $-70$
2. $70$
3. $35$
4. None of these

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$(x+a)^{n}$=$\sum \binom{n}{r} x^{n-r} a^{r}$ put x power zero find r then put r in equations

Ans=-70

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