例7.求函数 y=Isin x的导数 解:设ylnl,l=sinx,则 y=( u (sin x)x=.coSx cOSX sInx
结束 解 设y=ln u u=sin x 则 例7 求函数y=lnsin x的导数 x x x x u y u x u x tg sin cos cos 1 =(ln ) (sin ) = = = x x x x u y u x u x tg sin cos cos 1 =(ln ) (sin ) = = = x x x x u y u x u x tg sin cos cos 1 =(ln ) (sin ) = = =