f'+(1)=
lim |
x→0+ |
f(1+x)?f(1) |
x |
lim |
x→0+ |
af(x)?af(0) |
x |
f'-(1)=
lim |
x→0? |
f(1+x)?f(1) |
x |
lim |
x→0? |
af(x)?af(0) |
x |
所以,f'+(1)=f'-(1)=ab
所以,f(x)在x=1處可導(dǎo),且f′(1)=ab
故選:D.
lim |
x→0+ |
f(1+x)?f(1) |
x |
lim |
x→0+ |
af(x)?af(0) |
x |
lim |
x→0? |
f(1+x)?f(1) |
x |
lim |
x→0? |
af(x)?af(0) |
x |