This is optimization problem. If you explain it clearly and solve it step-by-step, I would be appreciated! Please do not write only answers. I need clear step by step solution. Thanks for your time.

Z : f($11$2) subject to g($1, $2) = c, Where c is a constant. Write the Lagrangian L for this problem. Show that at the optimum: dz*/dc = X\" where A denotes the Lagrange multiplier. Based on this result, what is the interpre- tation of the A