（5x-3y)(3y+5x)-(4y-3x)(3x-4y)

（5x-3y)(3y+5x)-(4y-3x)(3x-4y) （5x+3y)(3y-5x)-(4x-y)(4y+x)= （x+2)(x+3) (x-4)(x+1) (y+4)(y-2) (y-5)(y-3) (3x-4y)(5x-4y)-(7x-8y)(6y-5x) 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) x^8-x^7y+x^6y^2-x^5y^3+x^4y^4-x^3y^5+x^2y^-xy^7+y^8 3(x-y)-2(x+y)-5(x-y)+4(x+y)+3(x-y) 化简合并同类项 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 已知|2-x|与|x-y+4|互为相反数,求代数式3(x-y)-5(x-y)-3(x-y)+(y-x)-4(x+y)+3 数学题……555{(3x+y)(3x-y)-(x-5y)(5x-y)-(x-2y)²÷(-4x),x=-2.y 已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(