Question

I.F. of $\frac{dy}{dx}=\frac{x+y+1}{x+1}$ is:

• A. $\frac{1}{y+1}$
• B. $\frac{1}{x+1}$
• C. $log(x+1)$
• D. $log(y+1)$

Answer 1

Answer: (B)

$\frac{1}{x+1}$

$\frac{dy}{dx}=\frac{x+y+1}{x+1}$
$\frac{dy}{dx}-\frac{y}{x+1}=1$
$\Rightarrow I.F=e^{\int \frac{-1}{x+1}}dx$
$=e^{-log(x+1)}$
$=\begin{array}{c}1/x+1\end{array}$