# What are separable differential equations?

Sep 7, 2014

A separable equation typically looks like:
$\frac{\mathrm{dy}}{\mathrm{dx}} = \frac{g \left(x\right)}{f \left(y\right)}$.

By multiplying by $\mathrm{dx}$ and by $f \left(y\right)$ to separate $x$'s and $y$'s,
$R i g h t a r r o w f \left(y\right) \mathrm{dy} = g \left(x\right) \mathrm{dx}$

By integrating both sides,
$R i g h t a r r o w \int f \left(y\right) \mathrm{dy} = \int g \left(x\right) \mathrm{dx}$,
which gives us the solution expressed implicitly:

$R i g h t a r r o w F \left(y\right) = G \left(x\right) + C$,
where $F$ and $G$ are antiderivatives of $f$ and $g$, respectively.

For more details, please watch this video: