How to get a solution involving logs in the right form?

Question

How do I get

Solve[(1/9)^(r/2) == 1/n , r]

to give me

 Log[n]/Log[3]

and not

-Log[1/n]/Log[3]?

@b.gatessucks Perhaps you should consider posting working answers, however short they may be, as answers and not as comments. The list of seemingly unanswered questions is growing and growing. I won't hold it against you ;-)
You can get the result with Solve, you can do e.g. this Simplify[ Solve[ (1/9)^(r/2) == 1/n, r, Reals], n > 0].
@SjoerdC.deVries the alternative is someone collects all these answers in comments and produce 200 answers ;-)

b.gatessucks · Accepted Answer · 2012-12-13 08:14:13Z

up vote 1 down vote accepted

This does it :

Reduce[(1/9)^(r/2) == 1/n && n > 0, r, Reals]

(* n > 0 && r == Log[n]/Log[3] *)

answered Dec 13 '12 at 8:14

b.gatessucks
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1 Answer