How do I prove this?

Given that the function x, 3;, z) = xyz subject to the constraint 3:2 + y2 + 22 = 3 gives us 1 as the maximum value, show that for any nonnegative numbers a, b, c, we have 3 a+b+c x/b<. ac_ this is an inequality about the geometric mean hand side and arithmetic there a generalization of but we will not get to it>