Answer: (A U B) n (B n C') = {5, 8, 11}.
Step-by-step explanation: We are given the following sets :
U = {4, 5, 6, 7, 8, 9, 10, 11},
A = {5, 7, 9},
B = {4, 5, 8, 11}
and
C = {4, 6, 10}.
We are to find the following :
(A U B) n (B n C')
We know that for any two sets A and B,
A ∪ B contains all the elements present in set A or set B or both,
A ∩ B contains all the elements present in both A and B,
A - B contains all those elements which are present in A but not B
and
A' contains all the elements present in the universal set U but not A.
We will be suing the following rule of set of theory :
A ∩ B' = A - B.
Therefore, we have
![(A\cup B)\cap(B\cap C')\\\\=(A\cup B)\cap (B-C)\\\\=(\{5,7,9\}\cup\{4,5,8,11\})\cap (\{4,5,8,11\}-\{4,6,10\})\\\\=\{4,5,7,8,9,11\}\cap\{5,8,11\}\\\\=\{5,8,11\}.](https://img.qammunity.org/2020/formulas/mathematics/college/f4qdbtjb2dq6nk3hw0okxcgj0cgceoxnvg.png)
Thus, (A U B) n (B n C') = {5, 8, 11}.