### Gak: Modular Inverses!

Jun. 5th, 2003 01:33 pm*just*enough number theory that I know when one would be useful, and then I take

**forever**to calculate one. And Mathematica was of little help. I had to scour some web sites to determine that it uses a weird variant of its Solve function for linear congruence relations.

Here I was trying to get it to

**, which is the normal syntax (and which doesn't work) and it turns out I need to say**

`Solve[ Mod[17 a, 10000] == b, a ]`

**, a fact which is not mentioned in the reference for EITHER Solve or Mod.**

`Solve[ 17 a == b && Modulus == 10000, a]`