已知x=-3,y=1/3,求-x^2-(3/2x^2-1/3y)+(2/3-2x^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)
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
已知X-Y=3,求X-Y的2次幂减3X+3Y+1
已知3x-4y/2x+y=1/2 求x/y的值
已知|2x-3y|+|3x-y-1|=0,求x,y的值.
已知x=3分之1,y=二分之一,求代数式x-(x+y)+(x+2y)-(x+3y)+...-(x+13y)的值
已知x-3y=0,求(2x+y)/(x^2-2xy+y^2)X(x-y)
已知x/2=y/3=z/4,求下列各式 (1)(x+y+z)/x (2)(x-y+2x/(x-y-2z)
已知x²+|y+x|=x-1/4,求(3x+y)²(2x-y)²-(4x²+y&
y=(2x*x-2x+3)/(x*x-x+1),求值域?