Complex Analysis

To find the residue at pole it is very important to know the order of pole. In this page, we will learn when a singular point can be a pole and how to find the order of that pole. Definition of a Pole A point z=a is called a pole of a complex function f(z) … Read more

The Cauchy-Riemann equations in polar form are given as follows: ∂u/∂r = (1/r) ∂v/∂θ and ∂u/∂θ = – r ∂v/∂r if f(z)=u(r,θ)+iv(r,θ) is an analytic function. These C-R equations are very useful to test the analyticity of a complex function that can be expressed in polar co-ordinates easily. In this article, we learn the polar … Read more

The Cauchy Riemann equation states that if a complex function f(z) is differentiable at z=z0, then ifx(z0) = fy(z0). This is one of the main tool to test whether a complex function is differentiable or not. Here we state and prove Cauchy-Riemann equations along with some solved examples as an application. Statement of Cauchy-Riemann Equations … Read more

The complex analytic functions are one of the main objects to study in Complex Analysis. Here we learn the definition of analytic functions with examples, properties, and solved problems. Key concept to study analytic functions is complex differentiation. ℂ: = The set of complex numbers. Definition of Analytic Function A function f is called an … Read more

In the post, we will learn about complex differentiation where we study the derivative of functions of a complex variable along with some solved problems. ℂ := The set of complex numbers. Complex Differentiation: Definition Let D ⊆ ℂ be an open set and let f: D→ℂ be a complex function. The function f is … Read more

The following questions on Complex Analysis can be treated as an assignment as well as the suggestions on the upcoming exam. Q1: Find the real and the imaginary part of $f(z)=\dfrac{\overline{z}}{z}, z \neq 0$. Q2: Define the differentiability of a function f(z) at z=z0. Prove that f(z) = |z| is not differentiable at z=0. Q3: … Read more