lim(1-x)/(x2-1) x趋向于1

问题描述:

lim(1-x)/(x2-1) x趋向于1

分两种情况分析,当x>1时,其值是-1/2,当x

lim(1-x)/(x2-1)
=lim(1-x)/[(x-1)(x+1)]
因为x≠1,所以约分
=lim-1/(x+1)
x趋向于1

=lim-1/(1+1)
=-1/2