Posted: Apr 18, 2012 1:46 pm
Not really, but rearranging sets of tautologies is not a way to show more than that you have sets of tautologies. Working with trig identities is somewhat the same, but more challenging since there is not much beyond the Euler identity to make it appear that you have lots and lots of stuff to rearrange. I'm trying not to be hyperbolic, here.
Old Macdonald had a farm — e, i, e, i, Φ.