NAN DA XUE JING PIN KE CHENG 例6.设y=sin2x,求ym) 解:y=(sin2x)′=2 esInxcox=sin2x y=(sin2x)'=sin( 2x+). 2 (3) Sin(2x+2·)·2 丌 =sn2x+(m-1) OD 高等數粤例6. 设y = sin2x, 求 y (n) . 解: y' = (sin2x)' y'' =(sin2x)' = 2sinxcox = sin2x. ) 2 2 = sin(2 +   x ) 2 , 2 sin(2 2 (3) 2 = +    y x …… 2 . 2 sin 2 ( 1) ( ) −1        = + −  n n y x n 