Integrating factor of the differential equation $\cos x \frac{d y}{d x}+y \sin x=1$ is :
Answer & explanation
Correct answer: option 3
$\frac{d y}{d x}+y \frac{\sin x}{\cos x}=\frac{1}{\cos x}$
Here P = tan x, Q = sec x
∴ I. F. = $e^{\int \tan x d x}=e^{\log \sec x}=\sec x$
Hence (3) is the correct answer.