Proving Logical Truths

For those who, like myself, are fairly new to this game...

The 18 rules of inference can be found here:
http://www.barnzilla.ca/blog/?p=2152

The definition of a conditional proof can be found here:
http://en.wikipedia.org/wiki/Conditional_proof
(See the section on "Symbolic Logic"; it is the more helpful section.)

In an indirect proof you start by assuming that what you want to prove is false, and then conclude the contradiction (X & ~X) from that assumption.

Hint for this problem:
(written in white; highlight text below to see it...)

I have not done this yet, but it looks like your best move is to use an indirect proof. You have a rule of inference that says x –> y is equivalent to ~x V y. You probably want to use that twice here. It's so much easier to combine ANDs and ORs.