x=acos^3t,其中a不等于0求二阶导数?y=asin^3t

问题描述:

x=acos^3t,其中a不等于0求二阶导数?y=asin^3t

参数方程确定的函数的求导.
dy/dx=3asin^2tcost/[-3acos^2t sint]=-tanx
d^2y/dx^2=-sec^2t/[-3acos^2t sint]=1/[3acos^4t sint].