设y'=p 则y''=p(dp/dy) 怎么推出来的啊

问题描述:

设y'=p 则y''=p(dp/dy) 怎么推出来的啊

y'' = d(y')/dx = dp/dx = dp/dy * dy/dx = dp/dy * y' = dp/dy * p = p(dp/dy)