This is LaTeX code:

[latex]
\displaystyle
\frac{dz}{2-\frac{1}{z}-z}=
-\frac{1}{2}\frac{2\left( z-1\right)dz}{\left( z-1\right)^2}+\frac{dz}{\left( z-1\right)^2}
[/latex]