Process \(BC\) is isothermal \(\therefore\) \({W_{BC}} = R{T_2}.\ln \left( {\frac{{{V_2}}}{{{V_1}}}} \right)\)
Process \(CA\) is isobaric
\(\therefore {W_{CA}} = - \,P\Delta V\)\( = - \,R\Delta T\)\( = - \,R({T_1} - {T_2})\)\( = R({T_2} - {T_1})\)
(Negative sign is taken because of compression)