x=lnsint y=cost+tsint的二阶导数d^2y/dx^2
问题描述：
x=lnsint y=cost+tsint的二阶导数d^2y/dx^2
答
解题须知:dy/dx = y'(t) / x'(t)设:z = dy/dxz= dy/dx= y'(t) / x'(t)= t Cos(t) / Cot(t)= t Sin(t)dz/dx= z'(t) / x'(t)= (t Cos(t) + Sin(t)) / Cot(t)= Sin(t) (t + Tan(t))所以 d^2y/dx^2 = Sin(t) (t + Tan(t)...