The Rationals ArenÕt the Only OnesÉ

 

 

It was Pythagorus who said, all is number in the world,

ThatÕs why in ancient Greece the math geek always wound up with the girl.

He meant the markings on a ruler could in principle assign,

A fraction of whole numbers to each point on the line.

But then Hippasus came along and proved it simply wasnÕt true,

In fact you couldnÕt even do it for the square root of two.

Well PythagorusÕ buddies tossed him into the sea,

IÕm going to prove it for you now, but please donÕt do that to me!

 

            When I prove thatÉ

            The rationals arenÕt the only ones

            The rationals arenÕt the only ones

                        You need, you need, the reals.

 

Take the diagonal of a square with a side length of one,

If you could write it asp over q youÕd be done

Where p and q are standing in for integers who

Share no common factors but the one thatÕs less than two.

We will assume this and be forced to conclude something absurd,

ThatÕs called proof by contradiction as I hope youÕve all heard.

 

            ThatÕs how IÕm going to proveÉ

            The rationals arenÕt the only ones

            The rationals arenÕt the only ones

                        You need, you need, the reals.

 

IÕve got a question but donÕt worry cause its rhetorical,

ÒMust p be even or be odd or is it flexible?Ó

By PythagorusÕ Theorem it is very plain to see,

That p squared must be twice what q squared happens to be.

Thus p squared must be even so  p cannot be odd,

That makes it twice some number k if youÕre still with me please nod.

You plug 2k in for p each place that symbol occurs,

But to find out what you get youÕll have to hear the next verse.

            When we finally proveÉ

            The rationals arenÕt the only ones

            The rationals arenÕt the only ones

                        You need, you need, the reals.

A little algebra is all thatÕs necessary to see,

That q squared must be twice what k squared happens to be,

By now you must be feeling quite a sense of dŽjˆ vu,

So IÕll cut to the chase, qÕs a multiple of two.

At this climactic juncture letÕs review where weÕre at,

P to qÕs a ratio of even integerÕs that,

We very carefully assumed was completely reduced,

Yet this common factor 2Õs exactly what weÕve deduced.

ThereÕs your contradiction and in my opinion a whopper!

Those of you who brought champaign, nowÕs the time to pull the stopper.

You can tell the theoremÕs proved when angels burst into song,

And if you find my proof convincing wonÕt you please sing along

            Now that we all knowÉ

            The rationals arenÕt the only ones

            The rationals arenÕt the only ones

                        You need, you need, the reals.