2.lim_(xtoinfty)((x+1)/(x))^-(x)/(2)= （ ）

(2)lim_(xtoinfty)(x^2+cos^2x-1)/((x+sin x)^2)(2)$\lim_{x\to\infty}\frac{x^{2}+\c

lim_(xtoinfty)(cos x)/(x^2)=A. ∞B. 1C. 0D. 不存在

(15)lim_(xtoinfty)((2x+3)/(2x+1))^x+1.(15)$\lim_{x\to\infty}\left(\frac{2x+3}{2x

A.lim _(xarrow 1)dfrac ({x)^2+x-2}({x)^2-1}=lim _(xarrow 1)dfrac ((x-1)(x+2))((x

②lim_(xto+infty)(1+x)^(1)/(x).③lim_(xtoinfty)(1+(1)/(sqrt(1+x^2)))^x. ④lim_(xto

求极限：（1）lim _(xarrow 0)dfrac ({e)^2x-2(e)^x+1}({x)^2cos x}；（2）lim _(xarrow 0)dfra

(2) lim _(xarrow infty )((dfrac {2x+3)(2x+1))}^x+1;

(11)求lim_(xtoinfty)x^2[e^(1+(1)/(x))^(x)-(1+(1)/(x))^e^(x)].(11)求$\lim_{x\to\inf

(14) lim _(xarrow infty )((dfrac {x+2)(x+1))}^x;

求极限：lim_(xtoinfty)x^2[e^(1+(1)/(x))^(x)-(1+(1)/(x))^ex]求极限：$\lim_{x\to\infty}x^{