2)
a) 1 < x < 6
b) 9 < x <13
c) (1 , 2] U [ 9 ,10]
d) [20 ,40)
3)
[tex]\\C^B_A = A-B[/tex]
A={1,2,3,4,5,6} B={1,2,3} C={1,2,3,4,....}
a)
A-B=={4,5,6}
b)
C-B ={4,5,6....}
c)
C-A={7,8,....}
d)
B-A= { }
