例5.y=l(1+ex),求dy 解:dy=dh(1+ex) (1+ex) 1+e e x 1+e e Xe dx 1+
结束 解 例 5 ln(1 )2 x y= +e 求 dy 解 ( 1 ) 1 1 ln( 1 ) 2 2 2 x x x d e e dy d e + + = + = x e e e d x e x x x x 2 1 ( ) 1 1 2 2 2 2 2 + = + = dx e x exx 22 12+ = 解 ( 1 ) 1 1 ln( 1 ) 2 2 2 x x x d e e dy d e + + = + = x e e e d x e x x x x 2 1 ( ) 1 1 2 2 2 2 2 + = + =