lim X趋向于1 (1/x-1 - 2/x的平方-1）求极限,

lim(1-2x)^1/x x趋向于0 lim(x趋向于0)(x*cotx-1)/(x^2) lim(1+3x)^(2/x)x趋向于零 f(x)={x x=1}求lim x趋向于1- f(x) lim x趋向于1+ f(x) lim趋向于1 f(x)f(x)={2x-1 x0} 求lim x趋向于0- f(x) lim x趋向于0+ f(x) lim趋向于0 f(x) (1-x)tan(πx/2),lim 趋向于1, lim（x趋向于0）（1-cosx)/x^2 求lim x趋向于0(arctanx)/(x^2+1) lim(1+2tanx)^cotx (x趋向于0) lim(1-2x)^(1/x)=?lim下面是X趋向于0 lim(x趋向于1)[x/(1-x)-1/lnx] lim(1+e^1/x)^x,x趋向于+0 lim(arctan1/x)/(1/x),x趋向于无穷,为什么? lim(x趋向于无穷)(1+3/x)^(x-3) 求lim x趋向于0(e^x-x-1) x趋向于0 lim loga(1+x)/x= lim(1+3x)^3/x x趋向于0 lim f(x)=A x趋向于a limf(x^2)=A x趋向于a^2/1 求极限,lim(x趋向于1)(x^2-2x+1)/(x^3-x)