An equation involving specific heats $c_{\mathrm{p}}$, $c_{\mathrm{v}}$ is defined as
$$
c_{\mathrm{p}}-c_{\mathrm{v}}=T\left(\frac{\partial V}{\partial T}\right)\left(\frac{\partial P}{\partial T}\right)
$$
For the equation
$$
\frac{R T}{P}=V+\frac{K}{R T}
$$
( $K$ is a constant)
find $c_{\mathrm{p}}-c_{\mathrm{v}}$.