Question

Let $A$ and $B$ are two sets. Then $n(A^C\cap B^C)=$

• A. $n\left(U\right)–n(A\cap B)$
• B. $n\left(U\right)–n(A\cup B)$
• C. $n\left(U\right)–n(A^C\cup B)$
• D. $n\left(A\right)+n\left(B\right)$

Answer 1

The correct option is B $n\left(U\right)–n(A\cup B)$

$n(A^C\cap B^C)=n(A\cup B{)}^C=n(U)–n(A\cup B)$