Y by NO_SQUARES, mihaig, hankabal, Schur-Schwartz, LoloChen, ys-lg, kingu, Tastymooncake2, Dtong08_math, cubres
There is an inequality marathon now, but the problem is too hard for me to solve, let's start a new one here, please post problems that is not too difficult.
P1.
Find the maximum value of
, such that for 

P1.
Find the maximum value of


