JJ(x2+ y)dxdy=SU2(x2+y)dykdx 「n x(x-x)+a(x-x]dx 2 C=y 33 140 0≤y≤1 LY一型] 0.20.40.60.8 ∫x2+y)d=m(x2+y)帅 33 140 上一页下一页返回 + D (x y)dxdy 2 x y dy dx x x [ ( ) ] =   + 1 0 2 2 x x x (x x )]dx 2 1 [ ( ) 2 4 1 0 2 = − + −  . 140 33 = 2 y = x 2 x = y ［Y－型］         y x y y 2 0 1  + D (x y)dxdy 2 x y dx dy y   y = + 1 0 2 2 [ ( ) ] . 140 33 =