求极限Lim(x→0)1/xsinx-1/xtanx

问题描述:

求极限Lim(x→0)1/xsinx-1/xtanx

原极限=1/xtanx(1/cosx-1)
=1/xtanx·(1-cosx)/cosx
1/x^2·0.5x^2/cosx
=0.5