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)

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) 高数中若dy/dt=(dy/dx)*cost 那么d^2 y/dx^2 怎么求 参数方程的二阶导数中d^2y/dx^2=(d/dx)(dy/dx)=(d/dt)(1/dx/dt)(dy/dx),是一个 参数方程求导这个问题怎么解释 d^2y/dx^2=[d/dt(dy/dx)]/dx/dt 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+( x=f(t) y=g(t) 为什么dy/dx=(dy/dt)*(dt/dx) dx/dt=x+2y ,dy/dt=2x+y 求方程组dx/dt=-y dy/dt=2x=3y的通解 求方程组的通解：dx/dt=y,dy/dt=2x+y 如图.令x=e^t,为什么y''x^2=(d^2y)/(dt^2)-dy/dt? y= ∫[0,x](t-1)^3(t-2)dt,dy/dx(x=0) dx/dt=6t+2,dy/dt=（3t+1）sin（t^2）,求d^2y/dx^2