Hi everyone! I'd really appreciate if I could get pointed in the right direction as I am a brand new maple user.

So im trying to solve this constrainted optimization problem (See picture) using Maple symbollically. I believe I should have a closed form solution given I can substitute the one constraint into the objective function. Specifically closed form solutions for the three phi variables.

Can someone point me in the right direction as to how I should go about this? I've already taken first order conditions and tried to using the solve() function to no avail, realizing my sytem of equations weren't linear );.