(4x-5y)^2 (4x+5y)^2
1) (2x+5y)(2x-5y)(-4x^2-25y^2) 2) [(x+y)(x-y)-(x-y)^2+2y(x-y
(x+2)(x+3) (x-4)(x+1) (y+4)(y-2) (y-5)(y-3)
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
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
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
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
数学题……555{(3x+y)(3x-y)-(x-5y)(5x-y)-(x-2y)²÷(-4x),x=-2.y
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
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y