MHB Problem of the Week # 163 - May 12, 2015

[Ackbach]

Here is this week's POTW:

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Construct a formal proof of the following propositional statement: $(P\to (Q\to R)) \leftrightarrow ((P\land Q)\to R)$. Here $\to$ means "implies", $\leftrightarrow$ means "if and only if", and $\land$ means "and". Make sure to mention what deductive system you are using (Copi's 19 Rules, Natural Deduction, etc.).

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Remember to read the http://www.mathhelpboards.com/showthread.php?772-Problem-of-the-Week-%28POTW%29-Procedure-and-Guidelines to find out how to http://www.mathhelpboards.com/forms.php?do=form&fid=2!

 

[Ackbach]

No one answered this week's POTW. Here is my solution:

Spoiler

This is a Fitch-style proof using natural deduction.

View attachment 4383