设x=【1/3】y,求【3y/x+3y】+【x/3y-x】-【6xy/9y²-x²】的值.
x/y=3,求x²+y²-xy/x²-y²的值.
已知XY.Y=-3,求-XY(X.X.X.Y.Y.Y.Y.Y.Y.Y-3.X.X.Y.Y.Y.Y.Y-Y)的值.(过程完
已知x/y=2,求x²-xy+3y²/x²+xy+6y²的值
1/x+1/y=5,求2x-3xy+2y/x²+xy+y的值
已知x-3y=0,求(x²-2xy+y²/x-y)-2y的值
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
已知3x*+xy-2y*=0,求(x/y)-(y/x)-(x*+y*)/(xy)的值.*是平方
已知:6x²-7xy-3y²+14x+y+a=(2x-3y+b)(3x+y+1)求a,b的值
已知x+y=3 xy=-5 求x设abc=1 求x²+3xy+2y²/x²y+2xy
已知xy=-2,x-y=3,求(x+y)(x-y)-y平方+(x-y)平方-(6x2y-2xy平方)/2y的值
已知xy=2,x-y=3,求(x+y)(x-y)-y^2-(6x^2y-2xy^2)/2y的值.
当x=2,y=-1时,求代数式(x+y)(x-y)+(x-y)²-(x²-3xy)的值