Variables Separable Function
Definition
For a multivariable function, if there exists an $g_{i}$ that satisfies the following equation $f$, it is said to be separable in variables.
$$ f(x_{1}, x_{2}, \dots, x_{n}) = g_{1}(x_{1}) g_{2}(x_{2}) \cdots g_{n}(x_{n}) $$
Description
In simple terms, separating variables means expressing something as a product of functions that depend only on each variable. This assumption is often made when solving differential equations.