若2x−y+|y+2|=0
若2x−y+|y+2|=0
设x>1,y>0,若x^y+x^-y=2根号2,则x^y-x^-y等于
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
若3x-5y=0,则x+y/x=(),x-y/y=(),2x-3y/2x+3y=( )
若实数x,y满足x≥1x+y≤4x−2y+c≤0
若3x-4y=0,则x/y=______,(x-y)/y=______,(3x+2y)/(2x+3y)=_____.
设m为实数,若{(x,y)|x−2y+5≥03−x≥0mx+y≥0⊆{(x,y)|x
若:x+2y=62x+y=9
设2x−yx+y=3,其中x,y≠0,则(2x−3y)3−(3x−2y)3(4x+2y)3−(x−7y)3=( )
若实数x,y满足{2x-y>=0,