limx→∞ (x^2-x+1)(3-sinx)/x^3+2
问题描述：
limx→∞ (x^2-x+1)(3-sinx)/x^3+2
答
lim (x^2-x+1)(3-sinx)/(x^3+2)
= lim (1-1/x+1/x^2)(3-sinx)/(x+2/x^2) = 0