A=2x^5-3x^2 y^3+2y^5,B=2x^2+xy-3y^2,C=x^2-xy-7y^2,且A+D-[B-(C-A)]=0,求D

已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) (x-2y)^5=a0(x+2y)^5+a1(x+2y)^4*y+a2(x+2y)^3*y^2+a3(x+2y)^2*y^3+a4(x+2y)y^4+a 如果方程组x-y=a-3,2x+y=5的解x、y满足x>0,y 5a(x-y)^2+10a(y-x)^3 1、(-y^3)^5/y^3/ y^2+2(-y)^102、(x-y)^7/(y-x)^6+(x+y)^3/(x+y)^23、已知X^a=5,x^b=3,求X^(3a-2b)的值 x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 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 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 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:5(x-y)+2(x+y)-3(x-y) {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? (2x-3y)-(5x-y) (2X-3y)-(5x-y) (2x-5y)(3x+y) 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y)