13–
Direct Proof
Note:
The tilde (~) is used to denote a logical inversion, or NOT, operation.
The
symbol v is used to represent the OR operator, while the ^ symbol
represents the AND operator.
For
problems 1-5, use truth tables to determine whether each argument is valid.
1. p r
p q
------------
p (r ^ q)
2. p (r v q)
r ~q
------------
p r
3. p r
r q
------------
q
4. ~r ~p
r
------------
p
5. p r
r q
p
------------
q