f(x)在点x处可导,且lim f(x-3h)-f(0)/h =1,则F'(x)=?h-0_数学解答

f(x)在点x处可导,且lim f(x-3h)-f(0)/h =1,则F'(x)=?h-0

人气：472 ℃　时间：2020-05-04 09:55:03

解答

lim f(x-3h)-f(x)/h
=(-3) lim ( f(x-3h)-f(x) )/(-3h)
=(-3) lim ( f(x-3h)-f(x) )/(-3h -0)
=(-3) f'(x)
即 (-3) f'(x)=1
f'(x)= -1/3