SOLUTION: I need help annotating this proof because I really dont understand. 1. ~H ∨ F 2. F → J 3. ~~H ∴ ~F ∨ J 4. F

Algebra ->  Proofs -> SOLUTION: I need help annotating this proof because I really dont understand. 1. ~H ∨ F 2. F → J 3. ~~H ∴ ~F ∨ J 4. F      Log On


   

Question 1039399: I need help annotating this proof because I really dont understand.
1. ~H ∨ F
2. F → J
3. ~~H ∴ ~F ∨ J
4. F
5. J
6. ~F ∨ J
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
  1. ~H ∨ F 
  2. F → J 
  3. ~~H       ∴ ~F ∨ J 
  4. F           1,3, Disjunctive syllogism 
  5. J           2,4, Modus ponens  
5.5. J ∨ ~F        5, Addition
  6. ~F ∨ J      5.5, Commutation.  

[Notice I put in an extra step, numbered 5.5.  Maybe 
your professor considers ~F ∨ J and J ∨~F to be to 
same without bothering with commutation.  

Edwin