Which of the following intervals represents the set (1,4) u [2,6]?
a. (1,6]
b. (4,6]
c. [2,4)
d. (2,6]
show work,
!

Set is a sum of two intervals :(1,4) u [2,6] 
In the first interval it is open on both sides so 1 and 4 don't belong to this interval, the second is closed so both 2 and 6 belong to interval and numbers between 2 and 6
We can write it as 1<x
summing both sets we have one set: (1,6]
so
a) represent our set
b) also represent because all numbers between 4-6 and 6 are in our set
c)also represent, all numbers are in main set
d)also represent