I'm pretty new to the topic of natural deduction using the Fitch method. I found a very helpful site (http://proofs.openlogicproject.org/) in which you can construct your proofs, but I'm having a lot of trouble with the following:
I get as far as the proof for P but I'm not sure how to then use P to further the proof. I've done a lot of scouring on the net but I just cannot figure out how to continue. Any help would be appreciated.
Thanks
Hint
From $P \land Q$ you have correctly derived both $P$ and $Q$.
Now use $Q$ with $Q \to R$ to derive $R$ and conclude with $P \to R$ by $\to$-intro.
The same wit the other disjunct, in order to use $\lor$-elim to conclude with $P \to R$.