Tag: different forms of theoretical statements

Questions Related to different forms of theoretical statements

Without using truth , whether
$\left[ {p\Delta \left( { \sim q\Delta r} \right)} \right]V\left[ { \sim r\Delta  \sim q\Delta p} \right] \equiv p$

  1. True

  2. False


Correct Option: B

Solve it:-
$\left( {p \to q} \right) \to [\left( { \sim p \to q} \right) \to q]$

  1. Tautology

  2. Contradiction

  3. Contingent

  4. Not statement


Correct Option: A
Explanation:
$Y=\left( p\longrightarrow q \right) \longrightarrow \left[ \left( \sim p\longrightarrow q \right) \longrightarrow q \right]$
Method : TRUTH TABLE [  ALWAYS PREFERABLE]

 $p$  $q$  $p\longrightarrow q$  $\left( \sim p\longrightarrow q \right) $  $\left[ \left( \sim p\longrightarrow q \right) \longrightarrow q \right]$  $Y$
 $1$  $0$  $0$  $1$  $1$ $1$ 
 $1$  $1$  $1$  $1$  $1$  $1$
 $0$  $0$  $1$  $0$  $1$  $1$
 $0$  $1$  $1$  $1$  $1$  $1$
As the result is always TRUE $\left(i.e. 1\right)$;
$\left( p\longrightarrow q \right)\longrightarrow \left[ \left( \sim p\longrightarrow q \right) \longrightarrow q \right]$ is Tautology.

A. Tautology



















Let $p$ and $q$ be two propositions given by
$p$ : The sky is blue.
$q$ : The milk is white.
Then $p\wedge q$ will be

  1. The sky if blue or milk is white

  2. The sky is blue and milk is white

  3. The sky is white and milk is blue

  4. If the sky is blue then milk is white


Correct Option: B
Explanation:

$p \wedge q$ means statement p and q
=> The sky is blue and  milk is white.

Let $p$ and $q$ be two propositions. Then the contrapositive the implication $p\rightarrow q$

  1. $\sim q\rightarrow \sim p$

  2. $\sim p\rightarrow \sim q$

  3. $q\rightarrow p$

  4. $p\leftrightarrow q$


Correct Option: A
Explanation:

the contrapositive of $p\to q$ is $\sim q\to \sim p$

Consider the following statements 
$p$:you want to success
$q$:you will find way,
then the negation of $\sim (p\vee q)$ is

  1. you want of success and you find a way

  2. you want of success and you do not find a way

  3. if you do not want to succeed then you will find a way

  4. if you want of success then you cannot find a way


Correct Option: A

Which of the following statements is a tautology

  1. $\left( { \sim p \vee q} \right) - \left( {p \vee \sim q} \right)$

  2. $\left( { \sim p \vee \sim q} \right) \to p \vee q$

  3. $\left( {p \vee \sim q} \right) \wedge \left( {p \vee q} \right)$

  4. $\left( { \sim p \vee \sim q} \right) \vee \left( {p \vee q} \right)$


Correct Option: C

Which of the following is a logical statement?

  1. Open the door

  2. What an intelligent student!

  3. Are you going to Delhi

  4. All prime numbers are odd numbers


Correct Option: D
Explanation:

The above $3$ statements are basic statements.

But the $4$ statement is a logical statement.
All prime numbers are odd numbers.

The proposition $\left( {p \wedge q} \right) \Rightarrow p$ is 

  1. neither tautology nor contradiction

  2. A tautology

  3. A contradiction

  4. Cannot be determined


Correct Option: B

The statement $p \to (q \to p)$ is equivalent to 

  1. $p \to q$

  2. $p \to (q \vee p)$

  3. $p \to (q \to p)$

  4. $p \to (q \wedge p)$


Correct Option: B

Which of the following is correct?

  1. $(~p \vee ~q) \equiv (p \wedge q)$

  2. $(p \rightarrow q) \equiv (~q \rightarrow ~p)$

  3. $~(p \rightarrow ~q) \equiv (p \wedge ~q)$

  4. $~(p \leftrightarrow q) \equiv (p \rightarrow q) \wedge (q \rightarrow p)$


Correct Option: D
Explanation:


$~(p \leftrightarrow q) \equiv (p \rightarrow q) \wedge (q \rightarrow p)$ is true, we show it by truth table using boolean expression.

1.$p\rightarrow q$=min(1,1+q-p)
2.$p\wedge q$=min(p,q)
3.$p\leftrightarrow q$=1-|p-q|

Now we draw or make truth table using these operations
L.H.S  

 p  q $p\leftrightarrow q$ 
 1


R.H.S 

p $p\rightarrow q$  $q\rightarrow p$   $(p \rightarrow q) \wedge (q \rightarrow p)$
1  1  1  1
1  0

L.H.S =R.H.S

$~(p \leftrightarrow q) \equiv (p \rightarrow q) \wedge (q \rightarrow p)$