Integrating factor of the differential equation $(x+1) \frac{d y}{d x}-y=e^{3 x}(x+1)^2$, is
Answer & explanation
Correct answer: option 4
We have,
$\frac{d y}{d x}-\frac{1}{x+1} y=e^{3 x}(x+1)$
∴ Integrating factor = $e^{-\int \frac{1}{x+1} d x}=e^{-\log (x+1)}=\frac{1}{x+1}$