✔ 最佳答案
1
Set y=x-1
x+1=y+2
lim(x->1-)_(x+1)/(x-1)
=lim(y->0-)_(y+2)/y
=-∞
2
lim(x->1+)_|x-1|/(x-1)
=lim(x->1+)_(x-1)/(x-1)
=1
lim(x->1-)_|x-1|/(x-1)
=lim(x->1+)_(1-x)/(x-1)
=-1
lim(x->1)_|x-1|/(x-1) 不存在
3
(a)
lim(x->1+)_f(x)=lim(x->1+)_(1-x)=0
(b)
lim(x->1-)_f(x)=lim(x->1-)_2x=2
(c)
不存在
4
(f+g)(x)=x^3+2x+(x-3)^(1/2)
f[f+g(x)]=f[x^3+2x+(x-3)^(1/2)]
=[x^3+2x+(x-3)^(1/2)]^3+2[x^3+2x+(x-3)^(1/2)]+[x^3+2x+(x-3)^(1/2)
-3]^(1/2)
5
y=3x+2
3x=y-2
x=(y-2)/3
f^(-1)(y)=(y-2)/3
f^(-1)(x)=(x-2)/3
6
lim(x->2)_5=5
7
lim(x->3)_√(x^2+16)/(2x-1)=√(9+16)/(6-1)=1
8
lim(x->3)_(x^2+5x-2)=9+15-2=22