The logical statement $(\sim(\sim \mathrm{p} \vee \mathrm{q}) \vee(\mathrm{p} \wedge \mathrm{r}))…

The logical statement $(\sim(\sim \mathrm{p} \vee \mathrm{q}) \vee(\mathrm{p} \wedge \mathrm{r})) \wedge(\sim \mathrm{q} \wedge \mathrm{r})$ is equivalent to
  1. $\sim \mathrm{p} \vee \mathrm{r}$
  2. $(p \wedge \sim q) \vee r$
  3. $(\mathrm{p} \wedge \mathrm{r}) \wedge \sim \mathrm{q}$
  4. $(\sim p \wedge \sim q) \wedge r$

Solution

$\begin{aligned} & {[\sim(\sim p \vee q) \vee(p \wedge r)] \wedge(\sim q \wedge r)} \\ & \equiv[(p \wedge \sim q) \vee(p \wedge r)] \wedge(\sim q \wedge r) & \Rightarrow \ldots[\text { De Morgan's law }] \end{aligned}$ $\equiv \mathrm{p} \wedge(\sim \mathrm{q} \vee \mathrm{r}) \wedge(\sim \mathrm{q} \wedge \mathrm{r}) \quad \ldots[$ Distributive law $]$ $\equiv p \wedge[(\sim q \vee r) \wedge \sim q] \wedge r^{\prime} .. [\text { Associative law] }$ $\equiv \mathrm{p} \wedge(\sim \mathrm{q}) \wedge\mathrm{r} \quad \ldots[$ Absórption law] $\equiv(p \wedge r) \wedge \sim q$ .. [Commutative and Associative law]

Asked in: MHT CET 2023 (11 May Shift 2)

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