Question 1193810
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    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</pre>