⑩天掌 Teaching Plan on Advanced Mathematics o 例1设z=e"sin,u=xy,=x+y,求2,0 ax ay 解 az a Ou az av ax au ax ay ax =e"sinp…y+e"cosp·1 =e ly. sin( +y)+cos(+y)I u azaz au az av ay au ay a y x yx y =e"sinx+e"cos·1 e- y[xsin(x+y)+cos(x+y) tianjin polytechnic dmivendityTianjin Polytechnic University Teaching Plan on Advanced Mathematics 例1 设 z e sinv , u x y , v x y , u = = = + , . y z x z     求 解 x z   e v u = sin y z   e v u = sin x v v z      + e v u + cos y v v z      + e v u + cos 1 1 z u v x y x y