Intersection and union of sets....so confused

[Lindagerr]

Set C ={y (The straight line means such that) y≥2} so the set C =y such that y≥ 2 so that set includes all numbers from 2 up

Set D= {y such that y>6} so the set D = includes all numbers above 6 ( I used seven but that does not account for intergers so it should be >6)

So CUD = {y≥2} because that set includes all of the numbers in C and all of the numbers that are in D but each number is only listed once no matter how many sets you have .

So C∩D ={y>6} because that set includes only the numbers that are in both sets.


If we had C= {y such that y≥2 and y≤9} that set would be {2,3,4,5,6,7,8,9} Assuming we are using only whole numbers.

If we had D= {y such that y>6 and y≤10} that set would be {7,8,9,10}


So with those C and D the CUD would be {y=2,3,4,5,6,7,8,9,10} because this is all the numbers that are in either set just written once.

and C∩D would be {y=7,8,9} because those numbers are in both sets


I hope this explains it better I found most of the keystroke shortcuts