Does anyone know why Ibuwan edited the second formula for v_refract on Feb 14, 2012? I believe this to be wrong; the formula worked before, (with two additions) and is broken now (with two subtractions). (171.66.163.219)

Hi IP,

I think this refers to snells law #Vector form. I changed the formula for a better understanding for symmetry. it used to read and i changed it to so both are actually equal. It would be interesting to see it work with only two additions, because i carefully verified my result. (not for this article, but for my work) so please feel free to correct if im wrong. Ibuwan (talk) 01:36, 8 May 2012 (UTC)Reply

== edit

Thanks for the explanation. It seems then that my problem is not with your edit, but that of an anonymous user last June:

 "Revision as of 12:35, 21 June 2011 (edit) (undo)
  130.75.117.49 (talk)"

Any ideas on this? — Preceding unsigned comment added by 76.21.113.53 (talk) 07:24, 8 May 2012 (UTC)Reply