COMEDK · Maths · 20. Sets and Relations
If \(n(A)=3\) and \(n(B)=7\) and \(A \subseteq B\) then the number of elements in \(A \cap B\) is equal to
- A \(0\)
- B \(7\)
- C \(3\)
- D \(10\)
Answer & Solution
Correct Answer
(C) \(3\)
Step-by-step Solution
Detailed explanation
Given that \(A \subseteq B\), every element of set \(A\) is also an element of set \(B\). By definition of intersection, \(A \cap B = \{x : x \in A \text{ and } x \in B\}\). Since \(A \subseteq B\), for any \(x \in A\), it follows that \(x \in B\). Therefore, \(A \cap B = A\).…
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