已知A={y满足y=x2-4x+6,x属于R,y属于N},B={y满足y=-x2-2x+7,x属于R,y属于N}.求A交

A={y满足y=x2-4x+6,x属于R,y属于N},
y=(x-2)²+2
A={2,3,4,5,6,7,8,9,...}
A={y|y>=2,y∈N}
B={y满足y=-x2-2x+7,x属于R,y属于N}.
y=-(x+1)²+8
B={0,1,2,3,4,5,6,7,8}
B={y|0