Cauchy's Integral Theorem | Mathquery
Cauchy's Integral Theorem: Statement : The theorem is usually formulated for closed paths as follows : Let U be an open subset of C which is simply connected . Let f: U-->C be a holomorphic function , and let γ be a rectifiable path in U whose start point is equal to its end point . Then ∮ f(z) dz = 0 γ Proof : Let us assume that the partial derivatives of a holomorphic function are continuous , the Cauchy Integral Theorem can be proved as direct sequence of Green's Theorem and the fact that the real and imaginary parts of f = u + i v must satisfy the Cauchy - Riemann equations in the region bounded by γ , and moreover in the open neighbourhood U of this region. ...