UnitTriangle[(ϕ^3 - π^(1/12) x y^2 z^3)/ϕ^3, (π^(1/12) x y^2 z^3 + ϕ^3)/ϕ^3]

Uh oh! Wolfram|Alpha doesn't run without JavaScript.

Please enable JavaScript. If you don't know how, you can find instructionshere.Once you've done that, refresh this page to start using Wolfram|Alpha.