关于垂足三角形有向面积的一些定理

On Some Theorems of Directed Area for Pedal Triangles

给出垂足三角形有向面积公式 ,并利用该公式获得垂足三角形的若干新结果和著名的西姆松定理 .

This paper gives a formula of directed area for pedal triangles. Using this formula, we obtain some new results of pedal triangles and the famous R.Simson Theorem.