Hi,

I'm stuck on a simple problem - I have the following equivalences:

(¬P^¬Q)v(R^Q)v(¬P^R)=(¬P^¬Q)v(R^Q)

I can see why it is so simply by seeing that the first two terms already account for the truth of the third under the possible permutations.

However, I cannot see how to derive the result just using the propositional logic laws/manipulations.

Thanks for your help!

Chris