Enthalpy derivation differential equation

Mardonio
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Homework Statement
A state equation for a certain gas is ##(P + b)v = RT## and its internal energy is ##u = aT +bv +u_o##

show that $$(\frac {\partial H} {\partial v})_P = \frac {C_p T} {v}$$
Relevant Equations
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Good evening,
unfortunately I'm pretty lost in this problem.

I tried to use the chain rule $$(\frac {\partial H} {\partial v})_P = (\frac {\partial H} {\partial T})_P (\frac {\partial T} {\partial v})_P$$ and using some Maxwell relations but it doesn't work very well.
I know that $$T = (\frac {\partial H} {\partial S})_P$$ but I don't know how I would get to the answer.

I would be very happy if somone helped me.

Thanks.
 
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All you need to do is to use the gas law. The Maxwell relation is unnecessary for this problem.
 
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