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The coefficient of \(x^{2012}\)  in the expansion of \((1-x)^{2008}\left(1+x+x^{2}\right)^{2007}\) is equal to _____.

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\((1-x)(1-x)^{2007}\left(1+x+x^{2}\right)^{2007}\)

\((1-x)\left(1-x^{3}\right)^{2007}\)

\((1-\mathrm{x})\left({ }^{2007} \mathrm{C}_{0}-{ }^{2007} \mathrm{C}_{1}\left(\mathrm{x}^{3}\right)+\ldots \ldots.\right)\)

General term

\((1-x)\left((-1)^{\mathrm{r}}{ \ }^{2007} \mathrm{C}_{\mathrm{r}}{ }^{3 \mathrm{r}}\right)\)

\((-1)^\mathrm{r} \ ^{2007} \mathrm{C}_{\mathrm{r}} \mathrm{x}^{3 \mathrm{r}}-(-1)^{\mathrm{r}}\ ^{ 2007} \mathrm{C}_{\mathrm{r}} \mathrm{x}^{3 \mathrm{r}+1}\)

\(3 r=2012\)

\(r \neq \frac{2012}{3}\)

\(3 r+1=2012\)

\(3 r=2011\)

\(r \neq \frac{2011}{3}\)

Hence there is no term containing \(\mathrm{x}^{2012}\).

So coefficient of \(\mathrm{x}^{2012}=0\).

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