2(x-3y)+(1/4x+5y)-3(1/4x-y)

化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² 5/4(x+y)(-x-y)^3*[-4/3(x-y)]*[-3/5(y-x)^2] 5x^3y(x-y)^3-10x^4y^3(y-x)^2因式分解 5x^3y(x-y)^3-10x^4y^3(y-x)^2 5X^3Y(X-Y)-10X^4Y^3(Y-X)^2因式分解 (2x-y)(3x-4y)-2(x-y)(2x-5y)简便运算 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 （x-y）^3×（y-x）^4+（x-y）^2×（y-x）^5 {x+y=1 ,xy=-6{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 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) 先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5 -5(x-2y+1)-(1-3x+4y)