阿宝乖
幼苗
共回答了22个问题采纳率:86.4% 举报
lim(x->0)[((1-x)^1/2+1/2x-cosx)/(ln(1+x)-x) ]
=lim(x->0)[(3x²/8+o(x²))/(-x²/2+o(x²))] (应用麦克劳林公式展开)
=(3/8)/(-1/2)
=-3/4
lim(x->∞)(x-x²ln(1+1/x))
=lim(x->∞)(x-x²(1/x-1/(2x²)+1/(3x³)+o(1/x³))) (应用麦克劳林公式展开)
=lim(x->∞)(x-x+1/2+1/(3x)+o(1/x))
=lim(x->∞)(1/2+1/(3x)+o(1/x))
=1/2
1年前
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