Khan/khan-exercises — pull request #83157 by petercollingridge (2013-09-30 13:17:57+00:00)
Title: Fix rational expression divide function bug

Remove call to non-existent divideByTerm function as mentioned by @mauk81 at https://github.com/Khan/khan-exercises/commit/48b8a46351910b2055d44c85036d2b65c1f8f946#commitcomment-4204795 and add more unit tests to cover more examples of division.