-Use the rules of inference and the laws of propositional logic to prove that each

argument is valid. Number each line of your argument and label each line of your proof

"Hypothesis" or with the name of the rule of inference used at that line. If a rule of inference is

used, then include the numbers of the previous lines to which the rule is applied. For the

arguments stated in English, transform them into propositional logic first.

a)

(10 marks)

(p q) r

r

q

---------------

p

b)

If I go rock climbing, then I am sore.

If I am sore, I stay in bed all day.

I did not stay in bed all day.

-----------------------------------------

I did not go rock climbing