(2x-3y)()=9y²-4x²
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知4x²+y²-4x-6y+10=0求(2/3x(√9x)+(y²√x/y³)
已知4x²+y²-4x-6y+10=0,求[(2/3)x√(9x)+y²√(x/y
已知4x²+y²-4x-6y+10=0,求(2/3√9x+y²√x/y³)-(x
函数f(x,y)=x²+y²-2x+4y+9的最小值
4x+5y=105,2x+3y=178,x,y等于
(2x-y)²-4(x-y)(x+2y)
化简:(2x-y)²-4(x-y)(x+y)
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
[(y-2x)(-2x-y)-4(x-2y)²]*2y,其中x=1,y=2
求值(x-2y)²-4(x-2y)+2(x-2y)²-3(x-2y),其中x=-1,y=2分之1
已知4x²-9y²=12,2x-3y=3,求x,y 谢谢啦