Definition
Info
Laurent series or Laurent expansion is a representation of function
. It is normally used for complex function if Taylor series doesn’t work.
and are constants. .
Principle part
We also can write the infinite sum with:
Where:
The negative powers of
is called Principle Part of
- If there exists a number
such that . Then is said to be a Pole of order a.k.a the Isolated Singularity of . - If
with and every terms , is called Removable Singularity of . - If there is infinite
in principle part are nonzero, then c is known as Essential Singularity of .