Maximum modulus principle plays an important role in the complex analytics, and it is a powerful tool in studying the analytic function. 摘要最大模原理在複變函數論中佔有重要的地位，是研究解析函數的有力工具。
Classical complex variable method is followed, but a new conformal mapping formula is proposed so that the exterior part of the parabolic crack is mapped into a unit circle. 採用了傳統的複變函數保角映射法，給出了一個新的保角變換公式，從而將拋物線曲裂紋外的區域映射到一個複平面的單位圓內。
The derivative of the composite function is the product of the derivatives of the components. 複合函數的導數是構成函數的導數之積。
