1. R ⊃ A / R ⊃ (A v W) 2. R ⊃ (A v W) 1,addition [Replacing A by A v W, sometimes called "disjunction introduction"] https://www.youtube.com/watch?v=IN9nUurGpsk https://en.wikipedia.org/wiki/Disjunction_introduction Edwin
Number | Statement | Line(s) Used | Reason |
1 | R ⊃ A | ||
:. | R ⊃ (A v W) | ||
2 | ~R v A | 1 | Material Implication |
3 | (~R v A) v W | 2 | Addition |
4 | ~R v (A v W) | 3 | Association |
5 | R ⊃ (A v W) | 4 | Material Implication |