-- Oct 26 In-Class Exercise Thread
A -> (B `∧ C)) -> D
By Implication Elimination:
`\neg`(`\neg`A V (B ∧ C)) V D
Distribute Negation:
(A ∧ (`\neg`B V `\neg`C)) V D
Distribute V:
((A ∧ `\neg`B) V (A ∧ `\neg`C)) V D
By DeMorgan:
(`\neg`A V B) ∧ (`\neg`A V C) ∧ `\neg`D
(
Edited: 2022-10-26)
A -> (B @BT@∧ C)) -> D
By Implication Elimination:
@BT@\neg@BT@(@BT@\neg@BT@A V (B ∧ C)) V D
Distribute Negation:
(A ∧ (@BT@\neg@BT@B V @BT@\neg@BT@C)) V D
Distribute V:
((A ∧ @BT@\neg@BT@B) V (A ∧ @BT@\neg@BT@C)) V D
By DeMorgan:
(@BT@\neg@BT@A V B) ∧ (@BT@\neg@BT@A V C) ∧ @BT@\neg@BT@D