首页 > 留学知识库

问题: 高等数学提帮忙啊55555

解答:

lim(x->0)[(tanx -x)/(x -sinx)]
= lim(x->0)[(tanx -x)'/(x -sinx)']
= lim(x->0){[(secx)^2 -1]/(1-cosx)}
= lim(x->0)[(1+cosx)(1-cosx)/(1-cosx)]
= lim(x->0)(1+cosx)
= 2