问题
填空题
计算化简：
|
答案
原式=
+6y (x+y)(x-y)
+2 x-y 3 x+y
=
+6y (x+y)(x-y)
+2(x+y) (x+y)(x-y) 3(x-y) (x+y)(x-y)
=6y+2x+2y+3x-3y (x+y)(x-y)
=
+6y (x+y)(x-y)
+2(x+y) (x+y)(x-y) 3(x-y) (x+y)(x-y)
=5(x+y) (x+y)(x-y)
=
．5 x-y
故答案为
．5 x-y