Làm tính trừ : x^2 / (x+y)(1-y) - y^2/(x+y)(1+x) - x^2y^2/(1+x)(1-y)

x2x+y1−y−y2x+y1+x−x2y21+x1−y=x21+x−y21−y−x2y2x+yx+y1+x1−y=x2+x3−y2+y3−x3y2−x2y3x+y1+x1−y=x2−y2+x3+y3−x3y2+x2y3x+y1+x1−y=x−yx+y+x+yx2−xy+y2−x2y2x+yx+y1+x1−y=x+yx−y+x2−xy+y2−x2y2x+y1+x1−y=x−y+x2−xy+y2−x2y21+x1+y=x+x2−y+xy+y2−x2y21+x1+y=x1+x−y1+x+y21−x21+x1+y=1+xx−y+y21−x1+x1+y=x−y+y2−xy21+y