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Consider the following statements:
$P :$ Ramu is intelligent
$Q $: Ramu is rich
$R:$ Ramu is not honest
The negation of the statement "Ramu is intelligent and honest if and only if Ramu is not rich" can be expressed as.
$(( P \wedge(\sim R )) \wedge Q ) \wedge((\sim Q ) \wedge((\sim P ) \vee R ))$
$(( P \wedge R ) \wedge Q ) \vee((\sim Q ) \wedge((\sim P ) \vee(\sim R )))$
$(( P \wedge R ) \wedge Q ) \wedge((\sim Q ) \wedge((\sim P ) \vee(\sim R )))$
$(( P \wedge(\sim R )) \wedge Q ) \vee((\sim Q ) \wedge((\sim P ) \vee R ))$
Solution
$P$ : Ramu is intelligent
$Q$ : Ramu is rich
$R$ : Ramu is not honest
Given statement, "Ramu is intelligent and honest if and only if Ramu is not rich"
$=(P \wedge \sim R) \Leftrightarrow \sim Q$
So, negation of the statement is
$\sim[(P \wedge \sim R) \Leftrightarrow \sim Q]$
$=\sim[\{\sim(P \wedge \sim R) \vee \sim Q\} \wedge\{Q \vee(P \wedge \sim R)\}]$
$4=((P \wedge \sim R) \wedge Q) \vee(\sim Q \wedge(\sim P \vee R))$