若x+y=3 ,x2-y2=24,则x-y=
若实数x,y满足3x2+2y2=6x,则x2+y2的最大值为______.
我做对了吗.x2(x-y)+y2(y-x)= x2(x-y)-y2(x-y)=x2-y2=(x+y)(x-y)
已知实数x,y满足x2+xy+y2=3,则x2-xy+y2的最小值
已知2x=3y,求xy/(x2+y2)-y2/(x2-y2)的值
x2-x-y2-y 解法:=(x2-y2)-(x+y) =(x+y)(x-y)-(x+y) =(x+y)(x-y-1)
若x-y=2,x2-y2=10,则x+y= ___ .
若x2-y2=100,x+y=-25,则x-y的值是( )
若实数x,y满足X2+y2-2X+4y=0,则x-2y的最大值为?
实数x、y满足3x2+2y2=6x,则x2+y2的最大值为( )
若x、y是有理数,设N=3x2+2y2-18x+8y+35,则N( )
已知x2+4x+y2-2y+5=0,则x2+y2=______.
解方程组:y2=x3-3x2+2x;x2=y3-3y2+2y