If A = {1, 2, 3} and B = {2, 3, 4}, what is |A ∩ B|?

If A = {1, 2, 3} and B = {2, 3, 4}, what is |A ∩ B|?

Correct Answer: 2

Step 1: Identify the sets A and B. A = {1, 2, 3} and B = {2, 3, 4}.
Step 2: Find the intersection of sets A and B. The intersection (A ∩ B) includes elements that are in both sets.
Step 3: Look at the elements in A: 1, 2, 3 and in B: 2, 3, 4.
Step 4: Identify the common elements in both sets. The common elements are 2 and 3.
Step 5: Write the intersection as a new set. A ∩ B = {2, 3}.
Step 6: Count the number of elements in the intersection set {2, 3}. There are 2 elements.
Step 7: Write the final answer. |A ∩ B| = 2.

Set Intersection – The intersection of two sets A and B, denoted A ∩ B, is the set of elements that are common to both A and B.
Cardinality of a Set – The cardinality of a set, denoted |S|, is the number of elements in the set S.