**
Step 1:**
**Cauchy’s
Theorem for a Triangle**
As a first
step in Cauchy’s theory of integration we consider the
closed curve as a triangle.
**
Step 2:**
**Cauchy’s
Theorem for a star-like domain**
As a
second more general step in Cauchy’s theory of integration
we consider the closed curve as a star-like domain.
**
Step 3:**
**Cauchy’s
Integral Theorem **
We now consider still a more general
step where the closed curve is a circle.
**
Step 4:**
**Cauchy’s
Integral Formula**
This generalizes Cauchy’s integral
theorem. |