详情如图所示,
有任何疑惑,欢迎追问
dz/dx=∂z/∂u du/dx + ∂z/∂v dv/dx
= -v/xu² + e^x /u
= -e^x/xln²x + e^x / lnx
= e^x(1 - 1/lnx )/ lnx
[㏑f(x)]'=[v(x)·㏑u(x)]'
f'(x)/f(x)=v'(x)·㏑u(x)+v(x)u'(x)/u(x)
y'/y=v'(x)·㏑u(x)+v(x)u'(x)/u(x)
y'=y[v'(x)·㏑u(x)+v(x)u'(x)/u(x)]
=u(x)^v(x)[v'(x)·㏑u(x)+v(x)·u'(x)/u(x)]