x^2(x+1)+y^2(x+1)=B(x+1)
(x+1)(x^2+y^2)=B(x+1)
B=x^2+y^2 (当芦余然若陪消滚x=-1 B就桥森是任意了)
=(a-b)(b-c)-(-1)(b-a)(-1)(c-b)xy
=(a-b)(b-c)-(a-b)(b-c)xy
=(a-b)(b-c)(1-xy)
(x+1)+y(xy+y)
=(x+1)+y²(御胡升卖x+1)
=(x+1)(1+y²)
B=1+y²镇笑拦
(a-b)(b-c)-(b-a)(c-b)xy
=(a-b)(b-c)(1-xy)