Question

微积分，在线等

Answer 1

5.
lim [f(x0-2h)-f(x0+3h)]/h
h→0
=lim (-5)[f(x0-2h)-f(x0+3h)]/[(x0-2h)-(x0+3h)]
h→0
=(-5)f'(x0)
=(-5)·2
=-10
选A
6.
f'(x)=[(x-1)²]'(x+1)³+(x-1)²[(x+1)³]'
=2(x-1)(x+1)³+3(x-1)²(x+1)²
=(x-1)(x+1)²[2(x+1)+3(x-1)]
=(x-1)(x+1)²(5x-1)
令f'(x)=0，得x=1或x=-1或x=1/5
集合为{-1，1，1/5}
选相应的选项即可。
7.
lim [10^(2x)-7^(-x)]/(2tanx-arctanx)
x→0
=lim [2xln10-(-x)ln7]/(2x-x)
x→0
=2ln10+ln7
选A

Answer 2

5 A