Sometimes an x makes no sense to be plugged into a
      function:
We must steer clear of dividing by 0,
      or taking even roots of negative numbers.

Chorus:
      Doh, Domain and Range, we need to understand-
      What can go in, what can come out are part
            of a function's plan!

We won't deny there are values of y a function cannot
    put out-
Like negatives from even roots or from absolutes,
      or 0 from a fraction with nonzero top.
(Repeat chorus)

And there's no doubt we must leave out values
      that can't happen:
So we'll ignore a bowling score beyond 0 and 300!
(Repeat chorus)