Latex Formula

temaire · May 14, 2008

How do you write the permutation and combination formulas using latex. This is the best I can do:

[tex]n_P_r=\frac{n!}{(n-r)!}[/tex]

cristo · May 14, 2008

You mean like this: [tex]n \choose r[/tex] or [tex]^n\mathrm{C}_r[/tex] ?

temaire · May 14, 2008

Yes, that's what I meant, but I am used to writing down like this:

http://img88.imageshack.us/img88/7682/formula2nj1.png [Broken]

cristo · May 14, 2008

Ok, how about this then: [tex]_n\mathrm{C}_r \hskip5mm _n\mathrm{P}_r[/tex]

temaire · May 14, 2008

Thanks, that's what I needed.

temaire · May 14, 2008

Out of curiosity, are you good at perms. and combs.? Because I have a question on the the Precalc. forum that hasn't been answered yet. If not, it's ok, because I can wait.