求极限lim(x→3)x^2-4x+3/x^2-9

分类: 作业答案 • 2021-12-18 21:48:29

问题描述：

答

lim(x^2-4x+3)/(x^2-9)
=lim(x-1)(x-3)/[(x-3)(x+3)]
=lim(x-1)/(x+3)
=lim(3-1)/(3+3)
=1/3