Question

For this partial derivative problem ( http://f.imgtmp.com/Yno68.jpg ) where this is the solution: ( http://f.imgtmp.com/NQjq6.jpg ). I don't get why I can't just do (I), (II), and (III) directly. If you're a teacher and graded this, would you require that I draw those trees as well as those equivalent equations with the = 0 or is the product of (I),(II), and (III) = -1 enough for full points?

Answer 1

Also, what's the point of the F(P,V,T) = f(P,V) part? I see how it can be true, I just don't see why it matters. Also, why not just take another variable from F and make that a function of the other two for example F(P(V,T),V,T) = f(V,T)? The point being, why was T(P,V) chosen?