‹ Back to the paper
Choose the correct option.
∫ (cos(log x))/x dx is equal to:
$\int \frac{\cos(\log x)}{x}\,dx$ is equal to:
- (a)$\log(\sin x) + C$
- (b)$\cos(\log x) + C$
- (c)$\log x + C$
- (d)$\sin(\log x) + C$
Answer
Answer
Correct option: (d)
Answer: (d) $\sin(\log x) + C$
Put $t=\log x$, $dt=\frac{dx}{x}$, so $\int\cos t\,dt=\sin t + C=\sin(\log x)+C$.