例1求lm SIn zx 3x size 2sin2x 2 解im lim x-0 3x 03·2t=nsim2x2 32x-102x3 例2求lim tan r x→少0y 解 tan x sinx 1 m x→0y x→>0cosx sInx =lim lim x→0xx→~0coSX例2 . tan lim 0 x x x→ 求 解 x x x x x cos 1 lim sin lim →0 →0 =  = 1. x x x x cos sin 1 lim 0 =  x → x x tan lim →0 0 sin 2 lim . x 3 x → x 例1 求 解 x x x 3 sin2 lim →0 x x x 3 2 2sin2 lim 0  = → x x x 2 sin2 lim 3 2 2 →0 = . 3 2 =