设x=e^(-t),变换方程x^2*d^2y/dx^2+x*dy/dx+y=0

已知 x=e^t ,dy/dx=dy/xdt .分析变换具体步骤 d^2y/dx^2=(d^2y/dt^2-dy/dt) 设函数y=y(x)由x=1-e^t和y=t+e^-t确定,求dy/dx和d^2y/dx^2 令x=cost,变换方程d^2y/dx^2-x/(1-x^2)*dy/dx+y/(1-x^2)=0 证明x^2(d^2y/dx^2)+a_1x(dy/dx)+a_2y=0 ,令x=e^t,方程可化成d^2y/dt^2+( d^2y /dx^2 - 24 =0 dy/dx -2y = e^-x 设函数y=y(x)由方程y+e^(x+y)=2x确定,求dx/dy 设x=e^-t y=e^-2t 求dy/dx 设x=3e^-t,y=2e^t,则dy/dx等于多少? dy/dx+(e^((y^2)+x))/y=0 作变换u=tany,x=e的t次幂 试将方程 x^2d^2y/dx^2+2x^2(tany)(dy/dx)^2+xdy/ 已知参数方程x=e^(2t)-1,y=2e^t,求dy/dx,d^2y/dx^2 设 {x=2t^3+2 y=e^2t-1 ,求dy/dx,d^2y/dx^2