[题目]设有数列(xn)与(yn),以下结论正确的是 ()-|||-A.若 lim _(narrow infty )(x)_(n)(y)_(n)=0, 则必有 lim _(narrow infty )(x)_(n)=0 或 lim _(narrow infty )(y)_(n)=0-|||-B.若 lim _(narrow infty )(x)_(n)(y)_(n)=infty 则必有 lim _(narrow infty )(x)_(n)=infty 或 lim _(narrow infty )(y)_(n)=infty -|||-C.若xnyn有界,则必有xn与yn都有界-|||-D.若xnyn无界,则必有xn无界或yn无界

→(a)→∞-|||-lim _(narrow infty )(x)_(n)=+infty lim _(narrow infty )(y)_(n)=infty

没数列(xn)有界,又 lim _(narrow infty )(y)_(n)=0.没数列(xn)有界,又 lim _(narrow infty )(y)_(n

已知 lim _(narrow infty )(a)_(n)=2 lim _(narrow infty )(b)_(n)=3已知 lim _(narrow in

设 (x)=lim _(narrow infty )dfrac ({x)^n+2-(x)^-n}({x)^n+(x)^-n} 则函数(x)=lim _(narr

1.利用数列极限的" -N 定义证明:-|||-(1) lim _(narrow infty )dfrac (1)({n)^2}=0;-|||-(2) lim

设(x)=lim _(narrow infty )dfrac ({x)^n+2}(sqrt {{2)^2n+(x)^2n}}，则(x)=lim _(narrow

设(x)=lim _(narrow infty )dfrac ({x)^2n-1+a(x)^2+bx}({x)^2n+1}-|||-+bx/，若(x)=lim

[题目]求值 lim _(narrow infty )(sqrt (n+1)-sqrt (n))

[题目]求极限: lim _(narrow infty )(sqrt ({n)^2+n}-n).

__-|||-lim _(narrow infty )([ sin (dfrac {pi )(4)+dfrac (1)(n))] }^n=( )A.