2x 2y=3.6,x y 3y=3.8求x y=?,x-y=?怎么计算
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)
方程式计算5X-2=Y 4X+3=Y 求X.Y
y=2x*arctan(y/x),求y‘’
计算(x+2y)(x-2y)-(x+2y)-(x-2y)(2y-x)=?
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
已知x=2+根号3,y=2-根号3,计算代数式(x+y/x-y-x-y/x+y)乘以(1/x^2-1/y^2)
已知4x=9y求(1)x+y/y (2)y-x/2x
[x(x-y)-y(x-y)+(x+y)(x-y)]÷2x其中x=2012 y=2013
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
2x-y=2,求[(x²+y²)-(x-y)²+2y(x-y)]÷4y