limx趋近于1(根号(x+3)-2)/(根号x-1)
问题描述:
limx趋近于1(根号(x+3)-2)/(根号x-1)
答
lim(x→1)(√(x+3)-2)/(√x-1)(分子有理化,分母有理化得)
=lim(x→1)(√(x+3)-2)(√(x+3)+2)(√x+1)/[(√x-1))(√(x+3)+2)(√x+1)]
=lim(x→1)(√x+1)/(√(x+3)+2)
=1/2