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VI. CHAPTER SIX: SENTENTIAL LOGIC TRUTH TREES
Use the truth-tree method to determine the validity/invalidity of the following argument
forms:
(1) 1. p~q
2. ~ (~ q~p) / p
(2) 1. (p q)r
2. ~ q~r/p
(3) 1. p q
2. p r
3. ~ q r / ~ p
(4) 1. ~ (p q)
2. q~p/q~p
(5) 1. (p q)r
2. ~ (r q)
3. ~ (r~p)/ p q
(6) 1. p q
2. ~ [p(~ r q)]
3. ~ p r /r
(7) 1. p(q r)
2. p s
3. ~ q~p/r
(8) 1. (~ p q) (~ r~q)
2. s(r p) / s r
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VI. SUGGESTED ANSWERS
(1) 1. p~qp
(2) 1. (p q)rp
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(5) 1. (p q)rp
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(8) 1. (~ p q) (~ r ~ q) p