\( \Rightarrow \left( {\frac{{dP}}{{dV}}} \right) = \frac{{ - P}}{V} = \) Slope of Isothermal curve
For adiabatic\(P{V^\gamma } = \)constant
\( \Rightarrow \frac{{dP}}{{dV}} = \frac{{ - \gamma P}}{V} = \) Slop of adiabatic curve slope
Clearly, \({\left( {\frac{{dP}}{{dV}}} \right)_{{\rm{adiabatic}}}} = \gamma {\left( {\frac{{dP}}{{dV}}} \right)_{{\rm{Isothermal }}}}\)