First time here? Checkout the FAQ!
0 votes

Answer the following:

Which of the following well-formed formulas are equivalent?

  1. $P \rightarrow Q$
  2. $\neg Q \rightarrow \neg P$
  3. $\neg P \vee Q$
  4. $\neg Q \rightarrow P$
asked in Mathematical Logic by Veteran (29k points)   | 94 views
A,B and C are equivalent

2 Answers

+3 votes
Best answer
  1. P→Q    = P'+Q
  2. ¬Q→¬P=Q+P'
  3. ¬PVQ   =P'+Q
    so A,B,C are equivalent .
answered by Veteran (19.9k points)  
selected by
0 votes
A,B,C are equavelent i.e. $P\rightarrow Q \equiv \sim P \vee Q$

A and C are equal because if $\rightarrow$ is true then Contradiction always true.
answered by Veteran (44.2k points)  
edited by
D is not equivalent
Already done
How D?
i was taken as  $\sim$(Q $\rightarrow$ P)
That is also not true.

I know that sir Or wil changes to And. thats why changed that.

Members at the site
Top Users Feb 2017
  1. Arjun

    4676 Points

  2. Bikram

    4004 Points

  3. Habibkhan

    3738 Points

  4. Aboveallplayer

    2966 Points

  5. sriv_shubham

    2278 Points

  6. Smriti012

    2212 Points

  7. Arnabi

    1814 Points

  8. Debashish Deka

    1788 Points

  9. sh!va

    1444 Points

  10. mcjoshi

    1444 Points

Monthly Topper: Rs. 500 gift card

20,788 questions
25,938 answers
21,923 users