要过程~~~!!!
1、(-x-y)(x-y)
2、(-x-y)(x+y)
3、(0.4x-3y)^2 -(-3x)·y
4、(1/3a-b)(-1/3a-b)-(-b)^2
5 . (a+b-2)(a-b+2)
6 . (x^n+2)^2
要过程~~~!!!
1、(-x-y)(x-y)
2、(-x-y)(x+y)
3、(0.4x-3y)^2 -(-3x)·y
4、(1/3a-b)(-1/3a-b)-(-b)^2
5 . (a+b-2)(a-b+2)
6 . (x^n+2)^2
(-x-y)(x-y) 只能帮你这一道了,抱歉
= -(x+y)(x-y)
=-x²-y²