Rationalizing Fractions
- To: mathgroup at smc.vnet.net
- Subject: [mg17087] Rationalizing Fractions
- From: price at math.wisc.edu (Adam Price)
- Date: Sat, 17 Apr 1999 03:34:55 -0400
- Organization: University of Wisconsin, Madison
- Sender: owner-wri-mathgroup at wolfram.com
Personally, I think rationalizing fractions is overrated. The curriculum here emphasizes it, so that is what my students learn. Yesterday I was in the process of making an answer key to a review sheet for Alg. 101, and found that Mathematica doesn't think much of the practice either. I tried Simplify, FullSimplify, and those two along with Together, Apart and ExpandAll in various orders, but, like me, Mathematica thinks that 5/Sqrt3 is just as good an answer as 5 Sqrt[3]/3. Is there a short command sequence that will do this? I thought of using Numerator[] amd Denominator[] to have it build the appropriate factor, but when I tried multiplying by conjugate/conjugate, it just cancelled, and I was back where I started. I could, of course, regroup, so it does the numerator multiplication first, but this is getting to be a pretty long expression. (If you are wondering why I didn't do it by hand - there were a dozen problems, already in Mathematica, and the output had to printed out too, so I thought "no problem....the computer will do this for me.) -Adam