Factor Principles/Disjunction on Right
Theorem
Formulation 1
$p \implies q \vdash \paren {p \lor r} \implies \paren {q \lor r}$
Formulation 2
$\vdash \paren {p \implies q} \implies \paren {\paren {p \lor r} \implies \paren {q \lor r} }$