Question

Negation of ''A is in Class $X^{th}$ or B is in $XI{I}^{th}$'' is

• A. A is not in class $X^{th}$ but B is in $XI{I}^{th}$.
• B. A is not in class $X^{th}$ but B is not in $XI{I}^{th}$.
• C. Either A is not in class $X^{th}$ or B is not in $XI{I}^{th}$.
• D. none of these

Answer 1

Answer: (B)

A is not in class $X^{th}$ but B is not in $XI{I}^{th}$.

$\sim (p\vee q)=\sim p\wedge \sim q$
negaion of "A is in $X^{th}$ and B is in $XI{I}^{th}$" is
"A is not in $X^{th}$ and B is not in $XI{I}^{th}$