Question

The solution for the differential equation $\frac{dy}{y}+\frac{dx}{x}=0$ is

• A. $\frac{1}{y}+\frac{1}{x}=c$
• B. $\log x.\log y=c$
• C. $xy=c$
• D. $x+y=c$

Answer 1

Answer: (C)

We have, $\frac{dy}{y}+\frac{dx}{x}=0$
On integrating both sides, we get
$\log y+\log x=\log c$
$\Rightarrow \log xy=\log c$
$xy=c$