如何证明函数商的求导法则,即(u/v)'=(u'v-uv')/v^2越请细越好?
问题描述:
如何证明函数商的求导法则,即(u/v)'=(u'v-uv')/v^2越请细越好?
答
令k=1/v
(uk)' = u'k+uk'
=u' * 1/v + u * (1/v)'
= u'*1/v - u* 1/(v^2)
=(u'v-uv')/v^2