Let A and B be subsets of R and let x be an accumulation pt of A union B. Show that either x is an acc. pt. of A or x is an acc. pt. of B.
What are you doing?
As I count them, this is the eighth straight posting of statements.
You need to tell us what is the point of each.
If you are asking for help, then you need to show work that you have done for yourself.
That we can better help with exactly where you having a difficulty.