I have to find the expansivity of a substance obeying the Dieterici equation of state using the cyclical relation. I understand what I need to do, but I'm having a problem with the partial derivatives of the equation of state. I was wondering if anyone could refresh me on how to take a partial derivative of this equation: P=(RT/v-b)e^(-a/RTv) Taking the partial derivative of P with respect to T is simply the product rule, correct? But when I have to take the derivative of T wrt v, or the der. of v wrt P, I have to solve the equation for T and v respectively, right? That is where I'm having the problem, with the variables in the exponent of e. Any help someone could give me would be greatly appreciated.