来自黄宇橙的问题
化简x2−y2x2−2xy+y2的结果是()A.x+yx−yB.x−yx+yC.xx−yD.x+yy
化简x2−y2x2−2xy+y2的结果是()
A.x+yx−y
B.x−yx+y
C.xx−y
D.x+yy


化简x2−y2x2−2xy+y2的结果是()A.x+yx−yB.x−yx+yC.xx−yD.x+yy
化简x2−y2x2−2xy+y2的结果是()
A.x+yx−y
B.x−yx+y
C.xx−y
D.x+yy
原式=(x−y)(x+y)(x−y)