Let a and B Be Two Sets Such that : N ( a ) = 20 , N ( a ∪ B ) = 42 and N ( a ∩ B ) = 4 N ( a − B ) - Mathematics

Question

Let A and B be two sets such that : \[n \left( A \right) = 20, n \left( A \cup B \right) = 42 \text{ and } n \left( A \cap B \right) = 4\] \[n \left( A - B \right)\]

Solution

Given:

\[n \left( A \right) = 20, n \left( A \cup B \right) = 42 \text{ and } n \left( A \cap B \right) = 4\]

\[ n(A - B) = n(A) - n(A \cap B)\]
\[ \Rightarrow n(A - B) = 20 - 4 = 16\]

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Types of Sets - Universal Set

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Q 5.2 Q 5.1 Q 5.3

Chapter 1: Sets - Exercise 1.08 [Page 47]

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RD Sharma Mathematics [English] Class 11

Chapter 1 Sets
Exercise 1.08 | Q 5.2 | Page 47

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