Question

已知集合A={(x,y)|y=-x+1} 集合B+{(x,y)|y=x2-1} 求A∩B

Answer 1

联立y=-x+1和y=x²-1,得：x²-1=-x+1

∴x²+x-2=0,即(x-1)(x+2)=0,∴x=1,或x=-2

当x=1时,y=-x+1=0；当x=-2时,y=-x+1=3

∴A∩B={(1,0),(-2,3)}