1.(x+y)²-4（x+y-1)2.(x-y)²+4xy3.(x-1)(x+3)+1

1.(x+y)²-4xy=( )²2.x²-（ ）+25y²=（ )²3.x²-8x²y²+16y四次方=（ ）²4.7.2²-2.8²= . （x+y)²-4(x+y-1) 因式分解2x(x-y)^4 - x²(x-y)² + xy(y-x)²RT 9(x-y)²+12(x²-y²)+4(x+y)² 因式分解 已知(x+y)²;=8,(x-y)²;=4,求x²+y² 计算x²-x/x²×x/1-x和x²-4y²/x²+2xy+y²÷x+2y/x²+xy x²-4y² x+2y---------- ÷ --------分数线x²+2xy+y² x²+xyx²-4y² x+2y----------÷--------分数线x²+2xy+y² x²+xy(x+2y)(x-2y)x(x+y)=----------------(x+y)(x+y)(x+2y)(x-y)x=------(x+y)这样对了吗? 2x-y=2,求[(x²+y²)-(x-y)²+2y(x-y)]÷4y 1.x^4+3x²y²+4y^4 2.x^4+4 3.x²-2x-a²+2a 4.(x+y)²-4x-4y+41.x^4+3x²y²+4y^4 2.x^4+4 3.x²-2x-a²+2a 4.(x+y)²-4x-4y+4 5.x(x-2)-a(a-2) 6.(x+y)²-4(x+y-1) 1.(8xy-x²+y²)-(x²-y²+8xy)2.(2x²-1/2+3x)-4(x-x²+1/2)3.3x²-[7x-(4x-3)-2x²] x²-4y²+x-2y因式分解 x²-4y²+x+2y因式分解 (x²-4y²)-(x+2y)怎样因式分解? 4x²-y²+2x-y 因式分解 9a²(x-y) +4b²(y-x) x²-4y²-x-2y 分解因式 x²-x-4y²+2y x²-y²+4x+6y-5＝