沿y x+ⅸx3,dz=(1+3ix2)ax 1+i 。(x2+2)=(x2+0+3x)k 「(x2-3x2+x2+3x 4 Bix 3645 0 36 又×少 620沿 3 y x = 3 2 z x ix dz ix dx = + = + , (1 3 ) 1 1 2 2 3 2 0 0 ( ) ( )(1 3 ) , i x iy dz x ix ix dx + + = + +   1 2 5 3 4 0 = − + + ( 3 3 ) , x x ix ix dx  3 6 4 5 1 0 3 3 1 3 3 ( ) 3 6 4 5 3 6 4 5 x x ix ix i i = − + + = − + + 1 17 6 20 = − + i