已知(a-2b)^2-2x-2y+1=0,则x+y=
已知(a-2b)^2-2x-2y+1=0,则x+y=
已知x=1/y,则(x-1/x)(y-1/y)等于 A、2x² B、2y² C、x²+y&
已知3x+2y=a,2x+3y=b,则(x+y)(x-y)=?
向量题:已知a=y-x,b=2x-y,|a|=|b|=1,a·b=0,则|x|+|y|=
已知集合A={(x,y)|2^(x+y)=8},B={(x,y)|log4 (x-y)=1/2},则A∩B等于
已知x,y∈R,向量a,b不共线,若(x+y-2)a+(x-y)b=0,则x=,y=?
已知集合A={(x,y)| (y-3)/ (x-1)=2,x,y∈R},B={(x,y)| 4x+ay=16,x,y∈
1.已知集合A={(x,y)|y=2x+1},B={(x,y)|y=x+3},a∈A,b∈B,求a
已知【x+y】/【2x+2y】=x+y/2x+2y=1/2 则x,y满足的条件是 A |x+y|>0 B m-3/m+1
已知集合A={(x,y)|y=x+m},B={(x,y)|y=-x^2+2x+1,0
已知集合A={(x,y)|x*x+mx-y+2=0},B={(x,y)|x-y+1=o,0
已知集合A={(x,y)|(y-2)/(x-1)=a+2,x,y∈R},B={(x,y)|(a²-4)x+(a