GO Classes Weekly Quiz 5 | Propositional Logic | Question: 11

Answer 1

Basically this question asking that find the options which can make all the condition true simultaneous

Option 1:

Let whenever the system s/w is upgraded == U

user can access the file again = A

can save file  = S
Now Option 1 is saying that  U→ ~A ,A→ S, U→ S

let U = T then T→ ~A =True => ~A = True => A =False
A→ S => False → S = True => S can be t=True Or False
U→ S => T→ S =True => S=True
so option 1 is consistent
Option 2: Similarly that comes out to be consistent

Comments

U→ ~A and A → S doesn’t mean  U → S (by transitive property)

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These were there statement given but the question was asking just one think that is there anyone condition what make U->S

And this is true by taking U as True check out my answer

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@kickassakash 

I don’t think the transitivity you mentioned holds. 

$U \rightarrow \neg A$ will have the following diagram.

 

 

 

 

 

 

 

$A \rightarrow S$ will have the following diagram

 

 

 

 

 

 

 

 

 

 

out of $3$ possible diagram f $U\rightarrow \neg A$ and  $A \rightarrow S$ the following possibility will disregard  $U\rightarrow S$