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

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Theorem

$p \lor \left ({p \land q}\right) \dashv \vdash p$


Proof

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

$\blacksquare$