15.4. Definitions in the Context of Sets

Try these first

1. 1.

   What is a null set?

   Hint

   Think of an empty box.

2. 2.

   Give an example of a singleton set.

   Hint

   Just one item inside the braces.

3. 3.

   What does the symbol ϕ represent?

   • A null set
   • A singleton set
   • A set with multiple elements

   Hint

   Think of it as an empty box.

4. 4.

   Is {1} a proper subset of {1, 2}?

   • True
   • False

   Hint

   Consider whether both sets are identical.

5. 5.

   Given the set A = {a, b, c}, determine the power set P(A) and its cardinality.

   Hint

   Consider all combinations of including or excluding each element.

6. 6.

   If we have sets A = {1, 2, 3} and B = {2, 3, 4}, determine A ∩ B and A - B.

   Hint

   Remember to identify common elements for intersection and only elements in A for set difference.