Hi dont know if this is the rite forum to ask a question on this but Im revising for an upcoming exam and using past papers to help me however they didnt give the answers to the past papers which really doesnt help!

So ive been working my way through the paper but have come across some questions im not sure on.

I will put them here and see if anyone can help me if you cant dont worry

The resolution inference rule could be written:
not P -> Q, Q -> R
not P -> R

Prove that this is a valid rule by constructing a truth table.

the symbols didnt seem to transfer over rite so i put them in myself as not and -> hope you understand and can help me thanks

Proof by truthtables are simple - you merely need to show that the
two sentences has the same truth value for each possible assignment
of the variables.
The sentences are:
S1 <=> (~P -> Q) ^ (Q -> R) <=> (P v Q) ^ (~Q v R)
and
S2 <=> ~P -> R <=> P v R
The variables: P,Q,R
You then construct a table
P | Q | R | S1 | P v Q | ~Q v R | S2
T . T . T . T .. T ......T ...... T
T . T . F ...
et.c., an exhaustive tabulation where S1 and S2 must match.