Absorption Laws (Logic)/Disjunction Absorbs Conjunction/Proof 2

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Theorem

$p \lor \paren {p \land q} \dashv \vdash p$


Proof

\(\ds p \lor \paren {p \land q}\) \(=\) \(\ds \paren {p \land \top} \lor \paren {p \land q}\) Conjunction with Tautology
\(\ds \) \(=\) \(\ds p \land \paren {\top \lor q}\) Conjunction is Left Distributive over Disjunction
\(\ds \) \(=\) \(\ds p \land \top\) Disjunction with Tautology
\(\ds \) \(=\) \(\ds p\) Conjunction with Tautology

$\blacksquare$