+59 For P = {8 , 12 , 13 , 15 }, Q = {16 , 11 }, and R = {4 , 6 , 9 , 11 }, find P ∪ (Q∩ R).
the answer is ___
+71 Q intersection R is { 11 }. Apologies,this site won't let me use intersection symbols.
P U {11 } is { 8 12 13 15 } U {11} which is
{ 8 11 12 13 15 } ,your answer.
You can also,and probably should,use set algebra for this. As below
P U (Q intersection R) = ( P U Q) intersection ( P U R) . You will get the same answer.
{ If anyone out there can tell me how to get maths symbols on this site,please do. This is getting quite frustrating. }
+9479 You can copy and paste the intersection symbol, like this one in the problem: ∩
If there is such a symbol for what you need, you can usually find it in a google search.
If you can't find one....you can use LaTeX to make most symbols. For example, typing " \cap " into LaTeX makes an ∩ . If you can't find the right symbol in the buttons at the top...the code you need might be in this post or this post. 
