f(x) = f(y)+f(x-y)+2y (1<=y<=x/2) f(1)=1
i know that f is about xlogx when y is x/2
but i cant prove xlogx is maximum
can someone help me? why cant it be bigger?
i have a question
f(x) = f(y)+f(x-y)+2y (1<=y<=x/2) f(1)=1
i know that f is about xlogx when y is x/2
but i cant prove xlogx is maximum
can someone help me? why cant it be bigger?