lim(x→0)=1-cosx/x^2这玩意得多少?最好解释下,感激不尽!

lim(x→0)(1/cosx)=? 求lim(1-cosx)/x^2求lim(1-COSX)/X^2X→0 lim(x→0)(e^x-cosx)/x=1? 已知lim(x→0) f(x)/(1-cosx) =2 求lim(x→0) [1+f(x)]^½ lim(x→0)(cosx)^(1/ln(1+x^2)) 求Lim(x→0)(sinx/x)^(cosx/1-cosx) lim x->0 cos(2x)-1 / cosx -1 = x趋于0 lim sinx-tanx/x^3=lim sinx/x×(cosx-1)/(x^2×cosx)是怎么通分的?x趋于0 lim sinx-tanx/x^3=lim sinx/x×(cosx-1)/(x^2×cosx)thank you limx→0(cosx)^(1/x^2)求解lim(x→0)((cosx)^(1/x^2)) lim {[(1+2x)^1/2(1-cosx)]/x^3}=?x→0 y=lim (x → 0) ( √1+xsinx - √cosx) / arcsin^2x=lim (x → 0) ( 1+xsinx - cosx) / x^2( √1+xsinx +√cosx) =1/2 lim (x → 0) 1-cosx /x^2+ sinx/x这最后那步是怎么得到的,麻烦说的详细点,描述公式, lim(x→0)[(secx)^2-1] /(1-cosx) lim(x→0)(1-cosx)/(xsinx)=? lim x→0(1+2cosx)^secx lim(x→0)(cosx-cos^2x)/x^2 lim（x→0） 1-cosx/x＋x lim(x->0)(ln(1+x)-x)/(cosx-1)=? lim (2sinx+cosx)^(1/x) 求极限 x→0用e^ln(2sinx+cosx)^(1/x) =(2sinx+cosx)^(1/x) 求