Show (p ∧ q) → q ≡ T by using table 6 and the first line of table 7

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I used the left side to attempt to prove it was T. Chart of Laws

(p ∧ q) → q ≡ T

(p ∧ q) → q

Using the first line in table 7

¬(p ∧ q) v q

D'Morgans Law

(¬p v ¬q) v q

Associative Law

¬p v (¬q v q)

Negation Law

¬p v T

Domination Law

T ≡ T

I was wondering if this is right since I felt that you can't do that with domination law. If anyone could double check thank you.

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Yes that's completely correct.

The domination law states that $q \lor T$ is always true for any statement $q$. So it's true especially for any negated statement $\neg p \equiv q$.

Another way to think about this is to consider:

$$(\neg p \lor T) \equiv \neg\neg (\neg p \lor T) \equiv \neg(p \land F) \equiv \neg F \equiv T$$

that is using the double negation law and then applying De Morgan's laws one time to use the domination law directly with the $\land$ operator.