a
$\int_{p_{0}}^{p} \frac{d p}{P}=-a \int_{0}^{v} d v$
$\ell n\left(\frac{p}{p_{0}}\right)=-a v$
$p=p_{0} e^{-a v}$
For temperature maximum p-v product should be maximum
${T}=\frac{{pv}}{{n} {R}}=\frac{{p}_{0} {ve}^{-{av}}}{{R}}$
$\frac{{dT}}{{d} {v}}=0 \Rightarrow \frac{{p}_{0}}{{R}}\left\{{e}^{-{av}}+{ve}^{-{dv}}(-{a})\right\}$
$\frac{{p}_{0} {e}^{-{dv}}}{{R}}\{1-{av}\}=0$
${v}=\frac{1}{{a}}, \infty$
${T}=\frac{{p}_{0} 1}{{Rae}}=\frac{{p}_{0}}{{Rae}}$
$\text { at } {v}=\infty$
${T}=0$