求极限lim{n[ln(n+1)-lnn] n→∞求极限lim{n[ln(n+1)-lnn] n→∞lim(x^3+x^2)/(x-2)^2 x→2limx^2sin1/x^2 x→0

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求极限lim{n[ln(n+1)-lnn] n→∞求极限lim{n[ln(n+1)-lnn] n→∞lim(x^3+x^2)/(x-2)^2 x→2limx^2sin1/x^2 x→0

求极限lim{n[ln(n+1)-lnn] n→∞求极限lim{n[ln(n+1)-lnn] n→∞lim(x^3+x^2)/(x-2)^2 x→2limx^2sin1/x^2 x→0
求极限lim{n[ln(n+1)-lnn] n→∞
求极限
lim{n[ln(n+1)-lnn] n→∞
lim(x^3+x^2)/(x-2)^2 x→2
limx^2sin1/x^2 x→0

求极限lim{n[ln(n+1)-lnn] n→∞求极限lim{n[ln(n+1)-lnn] n→∞lim(x^3+x^2)/(x-2)^2 x→2limx^2sin1/x^2 x→0
① 等价无穷小量替换:ln(1+t) t (t->0)
lim(n→∞) n[ln(n+1)-lnn]
=lim(n→∞) nln[(n+1)/n]
=lim(n→∞) nln(1+1/n)
=lim(n→∞) n*(1/n)
=1

∵ lim( x→2) (x^3+x^2) = 12 ; lim( x→2) 1/(x-2)^2 = +∞
lim( x→2) (x^3+x^2)/(x-2)^2 = +∞
③ 重要极限 【或等价无穷小量替换:sint t (t->0)】
lim(x->0) x^2sin1/x^2
=lim(x->0) sin(1/x^2)/(1/x^2)
= 1