高数求导!
发布网友
发布时间：2022-05-30 04:52
共1个回答
热心网友
时间：2023-08-05 17:16
dx/dt = -3e^(-t)
y=2e^t
dy/dt =2e^t
dy/dx = (dy/dt)/( dx/dt ) = -(2/3)e^(2t)
d/dt ( dy/dx ) = -(4/3)e^(2t)
d^2y/dx^2
=[d/dt ( dy/dx )] / (dx/dt)
= -(4/3)e^(2t) / [-3e^(-t) ]
=(4/9)e^(3t)
