设函数f(x)在x1处可导,则
问题描述:
设函数f(x)在x1处可导,则
h→0 lim f(x1-h)-f(x1)/-h=_______?
答
lim f(x1-h)-f(x1)/-h
=lim-[f(x1)-f(x1-h)]/(-h);
=lim[f(x1)-f(x1-h)]/h
=f'(x1).