Q102 / 180 · KCET 2007 · Mathematics
The value of the integral
$\int_{0}^{\pi / 2}\left(\sin ^{100} x-\cos ^{100} x\right) d x$ is
- A$\frac{1}{100}$
- B$\frac{100 !}{(100)^{100}}$
- C$\frac{\pi}{100}$
- Correct answerD0
Solution
Let $I=\int_{0}^{\pi / 2}\left(\sin ^{100} x-\cos ^{100} x\right) d x$
$$
\begin{aligned}
&=\int_{0}^{\pi / 2} \sin ^{100} x d x-\int_{0}^{\pi / 2} \cos ^{100} x d x \\
&=\left[\frac{(\sin x)^{101}}{101} \cdot \cos x\right]_{0}^{\pi / 2} \\
&-\left[\frac{(\cos x)^{101}}{101}(-\sin x)\right]_{0}^{\pi / 2} \\
&=0+0=0
\end{aligned}
$$
Hence, the correct answer is option: 'D'.