Argument principle
= Argument principle
{wiki}
If a meromorphic function has no zeros or poles on a positively oriented boundary $\gamma$, then
$$
\frac1{2\pi i}\int_\gamma\frac{f'}f\,dz=N-P,
$$
with zeros and poles counted by multiplicity.
= Argument principle
{wiki}
If a meromorphic function has no zeros or poles on a positively oriented boundary $\gamma$, then
$$
\frac1{2\pi i}\int_\gamma\frac{f'}f\,dz=N-P,
$$
with zeros and poles counted by multiplicity.