5x^2-(3x^2+5x^2)+(4y^2+7xy),其中x=-1 y=1-根号2先化简,再求值

因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) 5/4(x+y)(-x-y)^3*[-4/3(x-y)]*[-3/5(y-x)^2] (2x-y)(3x-4y)-2(x-y)(2x-5y)简便运算 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=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 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 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 化简x-2y+3x-4x+5x-...+2001x-2002x,急. *-----------------------------------------------*| 6 4 X | 8 X X | X X 5 || X X X | X X X | X 7 8 || X X X | X X X | X X X ||---------------+---------------+--------------- || X X X | X X X | 5 1 X || X X X | X 6 X | X X X || 8 X X | 3 5 X | 2 X X || 化简:5(x-y)+2(x+y)-3(x-y) 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 (2x+y)²+(x+3y)(x-3y)-x(5x+8y)因式分解 3(x-y)-2(x+y)-5(x-y)+4(x+y)+3(x-y) 化简合并同类项