Q85 / 160 · WBJEE 2011 · Mathematics
The number \((101)^{100}-1\) is divisible by
- Correct answerA\(10^4\)
- B\(10^6\)
- C\(10^8\)
- D\(10^{12}\)
Solution
\(\begin{aligned}\text {Hints: }
& (101)^{100}-1={ }^{100} \mathrm{C}_1 100+{ }^{100} \mathrm{C}_2 100^2+{ }^{100} \mathrm{C}_3 100^3+\ldots \ldots +{ }^{100} \mathrm{C}_{100} 100^{100} \\
& =100^2\left[1+{ }^{100} \mathrm{C}_2+{ }^{100} \mathrm{C}_3 100+\ldots \ldots .\right] \\
& =\left(10^4\right)
\end{aligned}\)
Hence, the correct answer is option: 'A'.