1. The problem statement, all variables and given/known data Can anyone help me to start with the Thermodynamic Identity: (∂s/∂T)_x>0 for all processes where x is an arbitrary intensive or extensive variable of of the system. 2. Relevant equations 3. The attempt at a solution I do understand that we have to exploit some property of the properties of the system.Say all of them are exact differential or so...But cannot understand how to do this Identity... Can anyone please help me to start with it?