Question 3: Let \(U=\{1,2,3,4,5,6,7,8,9,10\}\), \(A=\{2,4,6,8,10\}\), \(B=\{1,2,3,4,5\}\) and \(C=\{1,3,5,7,9\}\)
List the members of each of the following sets:
\((iv)\) \(\;\) \(A- B \)
Solution:
\(A- B =\{2,4,6,8,10\}- \{1,2,3,4,5\}\)
\(\ \ \ \ \ \ \ \ \ \ \ =\{6,8,10\}\)
Explanation:
Think of \(A−B\) as “what’s left in A when you subtract B”. You’re removing all elements from \(A\) that also appear in \(B\).