I am new to mathematica and this is my first question, so please forgive me if it is something trivial. I am solving a maximisation problem, and my foc is the following:
focsm = g (sg^2 + sm (-2 + 2 fg + 4 fm + 3 sm) + sg (-1 + fg + 3 fm + 4 sm)) +
B[1 - fg - fm - sg - sm] - (fm + sm) Derivative[B][
1 - fg - fm - sg - sm]
As you may notice, it involves the function B[.] and its derivative. Now, for me B[.] is a generic function, with first derivative positive and second derivative less or equal than zero. I need to impose the foc equal to zero, and solve for sm (or alternatively fm). I tried with the command Solve, but it doesn't work.
Solve[focsm == 0, sm]
If I give a functional form to B[.] (for example linear), everything works. How can I solve this?