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I have no idea where to start with this:

As far as I know the general pattern for this sort of proof is,

1) All atomic well-formed formulas (wffs) have some property P

2) From the assumption that immediate predecessors of any non-atomic wff A have P, so too does A.

3) Every wff A has P

and I have to:

Prove by induction on immediate predecessors (wff complexity) that

no wff using only the letters P, Q and the connectives ^,v is a tautology.

Any suggestions would be much appreciated.

Thanks in advance,

Stopwatch

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# Proofs by induction on immediate predecessors (well-formed formula complexity)

Can you offer guidance or do you also need help?

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