3x²+(-3/2x+1/3y²)(2x-2/3y) x=-1/3.y=2/3
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
(3x-y)^2+(3x+y)(3x-y),x=1,y=-2
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
2(x+y) 3x+3y=24 x+y/2x x y/2y= 1
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
(X-Y)²+(3X-2Y)(2X+Y)-X(6X-Y),其中X=½,Y=1(先化简再求值)
先化简,再求值:(3x-y)²+(3x+y)(3x-y),其中x=1,y=-2
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
计算3x[xy-2x(1/y-x/3]+3y(x²-y²)