Hi Lucifer. What is $\pi$? What is $A$? I think we are missing some context here.
– RustynSep 16 '17 at 22:32
π is just some function here that needs to be maximised. And A, as defined in the question, is the set of (x1,x2,x3) which meets the conditions.
– LUCIFERSep 17 '17 at 10:20