1.(8xy-x²+y²)-(x²-y²+8xy)2.(2x

网友回答

1、(8xy-x²+y²)-(x²-y²+8xy)=[8xy-(x²-y²)][8xy+(x²-y²)]
=64x²y²-(x²-y²)=64x²y²-x^4+2x²y²-y^4=66x²y²-x^4-y^4
2、 (2x²-1/2+3x)-4(x-x²+1/2)= 2x²-1/2+3x-4x+4x²-2
= 6x²-x-2.5
3、3x²-[7x-(4x-3)-2x²]=3x²-7x+(4x-3)+2x²
=5x²-7x+4x-3=5x²-3x-3
======以下答案可供参考======
供参考答案1:
（8xy-x²+y²)-(x²-y²+8xy)
=8撒啊就擦不好啊啊
=8973425928562958
供参考答案2:
1)[email protected][email protected]@[email protected]
[email protected]
@ @为平方2)[email protected]/[email protected]
[email protected]/2
3)[email protected]([email protected])
[email protected]+4x-3+2x
@ [email protected]
linkqlj 第一题错了吧初一那呢么南？
供参考答案3:
1题=8XY-X^2+Y^2-X^2+Y^2-8XY
=(8XY-8XY)-2X^2+2Y^2
=2Y^2-2X^2
2题=2X^2-1/2+3X-4X+4X^2-2
=6X^2-X-2.5
3题=3X^2-7X+4X-3+2X^2
=5X^2-3X-3