Guys in the following optimisation problem why are we not considering the partial derivate of K and L in the Lagrangian in the first two equations
1 Answer
when you are taking the partial derivative of the Lagrangian wrt l you are taking the other variables as constants, so they are derived away. You cannot do this with f(k,l) as this is a function with a l input
the same applies to the partial derivative of the Lagrangian wrt k
refer back to the rules of partial differentiation