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If \(\mathrm{n} > 1\) is an integer and \(\mathrm{x} \neq 0\), then \((1+\mathrm{x})^{\mathrm{n}}-\mathrm{nx}-1\) is divisible by
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\(\mathrm{x}\)
\(\begin{array}{r}\text {Hints: }
(1+\mathrm{x})^n={ }^n C_0+{ }^n C_1 x+{ }^n C_2 x^2+{ }^n C_3 \mathrm{x} 3+\ldots \ldots . \\
=1+\mathrm{nx}+\mathrm{x}^2\left({ }^n C_2+{ }^n C_3 \mathrm{x}+\ldots \ldots . .\right) \\
(1+\mathrm{x})^{\mathrm{n}}-\mathrm{nx}-1=\mathrm{x}^2\left({ }^n C_2+{ }^n C_3 \mathrm{x}+\ldots \ldots .\right)
\end{array}\)
(1+\mathrm{x})^n={ }^n C_0+{ }^n C_1 x+{ }^n C_2 x^2+{ }^n C_3 \mathrm{x} 3+\ldots \ldots . \\
=1+\mathrm{nx}+\mathrm{x}^2\left({ }^n C_2+{ }^n C_3 \mathrm{x}+\ldots \ldots . .\right) \\
(1+\mathrm{x})^{\mathrm{n}}-\mathrm{nx}-1=\mathrm{x}^2\left({ }^n C_2+{ }^n C_3 \mathrm{x}+\ldots \ldots .\right)
\end{array}\)
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