[b]Fact:[/b] If γ is a closed curve parameterized by [math]t[/math]∈ [ α , β ], the winding number of γ about [math]w[/math], is determined for any complex [math]w ∉γ([α,β])[/math] to be [br][center][math]\frac{1}{2\pi i}∮_C\frac{1}{z-w}dz[/math].[/center]