It is possible to do a truth table, but my instructor says we should be able to just reason it out:

> 
> $P\Rightarrow (Q\Rightarrow R)$ is equivalent to $(P\wedge Q) \Rightarrow R$.
> 
> 
> 

My instructor says something like, "The second statement just points out the underlying meaning of the first statement. They both rely on two assumptions--$P$ and $Q$. So, they are equivalent."

I do not quite understand how to reason it out. Could anyone explain it a little bit?