## What is Laurent series formula?

Laurent’s Series Formula γ can be any circle | w – z0| = r, inside the annulus. It means, r1 < r < r2. From the series, we can also say, ∑ n = 0 ∞ a n ( z − z 0 ) n. converges to the analytic function, when |z-z0| < r2.

## What is Laurent series in complex analysis?

In mathematics, the Laurent series of a complex function f(z) is a representation of that function as a power series which includes terms of negative degree. It may be used to express complex functions in cases where a Taylor series expansion cannot be applied.

**What is Laurents Theorem?**

noun Mathematics. the theorem that a function that is analytic on an annulus can be represented by a Laurent series on the annulus.

### Why do we need Laurent series?

The method of Laurent series expansions is an important tool in complex analysis. Where a Taylor series can only be used to describe the analytic part of a function, Laurent series allows us to work around the singularities of a complex function.

### Can a Taylor series be finite?

The Taylor’s theorem states that any function f(x) satisfying certain conditions can be expressed as a Taylor series: assume f(n)(0) (n = 1, 2,3…) is finite and |x| < 1, the term of. x n becomes less and less significant in contrast to the terms when n is small.

**Why do we use Laurent series?**

#### What is principal part of Laurent series?

The portion of the series with negative powers of z – z 0 is called the principal part of the expansion. It is important to realize that if a function has several ingularities at different distances from the expansion point , there will be several annular regions, each with its own Laurent expansion about .

#### What is meant by removable singularity?

In complex analysis, a removable singularity of a holomorphic function is a point at which the function is undefined, but it is possible to redefine the function at that point in such a way that the resulting function is regular in a neighbourhood of that point.

**What is the principal part of a Laurent series?**

with the series convergent in the interior of the annular region between the two circles. The portion of the series with negative powers of z – z 0 is called the principal part of the expansion.