`
Question:
Negation of the statement $(p \vee r) \Rightarrow(q \vee r)$ is:
Correct Option: 1
Solution:
$\because \sim(\mathrm{A} \Rightarrow \mathrm{B})=\mathrm{A} \wedge \sim \mathrm{B}$
$\therefore \sim((p \vee r) \Rightarrow(q \vee r))$
$=(p \vee r) \wedge(\sim q \wedge \sim r)$
$=((p \vee r) \wedge(\sim r)) \wedge(\sim q)$
$=p \wedge(\sim r) \wedge(\sim q)$