求lim(x^3(sin1/x-1/2*sin2/x)) x趋于无穷

lim(2x^2+1/3x-1)•sin1/x. X趋于无穷大,求极限 求lim(x^3(sin1/x-1/2*sin2/x)) x趋于无穷 求极限lim(x→0)(x^3sin1/x)/(1-cos^2x),要详细过程～ 求极限lim(x→0)[2sinx+x^2(sin1/x)]/ln(1+x) f(x)=(2+e^x)/1+e^2x)+ | x|sin1/x求 1)lim[x→+∞]f(x); 2)lim[x→-∞]f(x); 3)lim[x→∞]f(x) lim (x^2sin1/x) /sinx lim(x→0)(x*sin1/x)/x^2极限为什么不存在?lim(x→0)(x*sin1/x)/x^2= lim(x→0)1/x*sin1/x 为什么这两个无穷小量不可以比较呢 求lim[1+(sin1/x+cos1/x-1)]^x (x趋于无穷大) lim（ x^2 sin1/x）/x,也是求极限,x趋于0我的解法是lim（sin1/x)/(1/x),根据两个重要极限可以得知极限为1但是正确答案是0,想知道哪里不对 计算极限① lim(x→+∞) 1 / [ (√x^2+3x) - x ],② lim(x→1) (sinx-sin1)/(x-1) 求极限 lim{x→0}x2*sin1/x 求极限lim(x→2)(x^2-4)sin1/(x-2), 求极限lim{(x^2/sinx)×sin1÷x}x趋向0 求lim(x→0)[(x^2sin1/x)/sinx]能不能用罗必塔做? 求极限：lim[(x^2sin1/x)/tanx],x趋于0 求lim(x^2)·(sin1/x),x趋于0的极限 lim x-->正无穷 (x^2 sin1/x) 怎么算? 正无穷lim(x^2+x)sin1/x