已知全集I,集合A和B,求CIA∩B
问题描述:
已知全集I,集合A和B,求CIA∩B
(CIA即全集I中集合A的补集)
(1)I={实数对(x,y)},A={(x,y)|(y-4)/(x-2)=3},B={(x,y)|y=3x-2}
(2)I=R,A={a|二次方程ax^2-x+1=0有实根},B={a|二次方程x^2-ax+1=0有实根}
答
(1)y=3x-2 and (y不=3x-2 or x=0)CIA∩B = {(0,-2)}(2)CIA∩B = {a|二次方程ax^2-x+1=0没有实根且二次方程x^2-ax+1=0有实根}这个真简洁...- - ------------------1-4a=0a>1/4 and (a>=2 or a=2}...