lim SInx=1, lim sinaw)=1(dx)->0) x→>0x a(x) 例1求lim tanx x→>0x 解1 tanx -lim sinx -lim sinx. im- x->0x x-0 x COSx x>0 r x-0 COSX 例2求lim1=C0sx x→>0x 解 1-cOSx 2sin2 x lim -=lim m x->0x 2 x→>0X 2x->0x Sn、2 Im x-)0x 2 自 返回 下页 结束首页 上页 返回 下页 结束 铃 2 0 1 cos lim x x x − → = 2 2 0 2 2 0 ) 2 ( 2 sin lim 2 1 2 2sin lim x x x x x→ x→ = 1 sin lim 0 = → x x x  1 ( ) sin ( ) lim = x x a a (a(x)→0) 例 例 11 求 x x x tan lim →0  解 x x x tan lim →0 x x x x cos sin 1 lim 0 =  → 1 cos 1 lim sin lim 0 0 =  = → x → x x x x 解 解   x x x tan lim →0 x x x x cos sin 1 lim 0 =  → 1 cos 1 lim sin lim 0 0 =  = → x → x x x x 解  x x x tan lim →0 x x x x cos sin 1 lim 0 =  → 1 cos 1 lim sin lim 0 0 =  = → x → x x x x 解  x x x tan lim →0 x x x x cos sin 1 lim 0 =  → 1 cos 1 lim sin lim 0 0 =  = → x → x x x x  解 例 例 22 求 2 0 1 cos lim x x x − →  首页 2 1 1 2 1 2 2 sin lim 2 1 2 2 0 =  =         = → x x x  2 1 1 2 1 2 2 sin lim 2 1 2 2 0 =  =         = → x x x  2 0 1 cos lim x x x − → = 2 2 0 2 2 0 ) 2 ( 2 sin lim 2 1 2 2sin lim x x x x x→ x→ = 2 0 1 cos lim x x x − → = 2 2 0 2 2 0 ) 2 ( 2 sin lim 2 1 2 2sin lim x x x x x→ x→ =