# Please check those two production functions, they also seems to be quasiconvex?

Those two are generic production functions that we usually see, and I check the definition of quasiconvex and quasiconcave on wikipedia, and it seems those two graphs satisfy both definitions, and then so-called quasilinear. Then, I ponder why the production function we would generally assume to be quasiconcave only. Or I might misunderstand the definition or carelessly draw the wrong graph?

Appreciated any comment and help

• Is it a function with a single variable, $F(K)$? Aug 16 at 15:56
• Is it also monotonically increasing? Aug 16 at 15:56
• @Giskard Thank you for your reply. Both Yes. But I have no idea why these questions are related to quasiconcavity. What happens if we suppose they are two variables function, let's considered it as a 3D picture. are they still quasi-convex?
– LJNG
Aug 16 at 16:03

• Thank you for your reply. Is my two graphs also quasilinear, they seems also fit both difinition $f(tx+(1-t)y)\leq max\{f(x),f(y)\}$ and $f(tx+(1-t)y)\geq min\{f(x),f(y)\}$