Complex Modulus/Examples/3iz - z^2

Example of Complex Modulus
Let:
 * $w = 3 i z - z^2$

where $z = x + i y$.

Then:
 * $\cmod w^2 = x^4 + y^4 + 2 x^2 y^2 - 6 x^2 y - 6 y^3 + 9 x^2 + 9 y^2$