through the basic definition which inferred from the directional derivative of binary function,combine the concept of gradient,get the solution of directional derivative about inside normal and outside normal of a point on curve or surface,and extended this method to ternary function,and as its application,analyzed some examples in the end.%通过导出的二元函数方向导数的基本定义式,结合梯度的概念,得出了求解曲线、曲面上某点的内、外法线方向的方向导数的方法,并将这一方法推广到三元函数,作为其应用,最后分析了几个实例.
展开▼
