Hi, i am not to sure if i got this in the right section, but i was wondering if anyone could help me with this question below. If anyone can get me started on this or give me pointers on how to go about it.

A firms prodution function is Q(x,y,z) = 7*(Square root(x))*ln(4y) + 2ln(x+1) , where x,y,z are positive quantities of three inputs.

also T is the largest subset of R^3 positive. (couldnt get the symbol for R^3, sorry).. on which Q is a concave.

I need to find, in its simplest form, an inequality that defines T