Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Differential Equations

Question:

An integrating factor of the differential equation

$y \log y \frac{d x}{d y}+x-\log y=0$, is

Options:

$\log (\log y)$

$\log y$

$\frac{1}{\log y}$

$\frac{1}{\log (\log y)}$

Correct Answer:

$\log y$

Explanation:

We have, $\frac{d x}{d y}+\frac{1}{y \log y} x=\frac{1}{y}$

Integrating factor = $e^{\int \frac{1}{y \log y}} d y=e^{\log (\log y)}=\log y$