Homework Help: Logarithmic function #2

1. Jan 17, 2009

nvez

Hello again..

1. The problem statement, all variables and given/known dataI
I have to change this to one term only, the valid answer is: log (x + 1)

The term is: 2 log (x2 - 1) - log (x + 1) - 2 log (x - 1)

2. Relevant equations
Logarithmic laws:

x log n = log nx
log m - log n = log (m/n)

3. The attempt at a solution
I have tried dividing them but I don't see to be getting anywhere or anywhere close at all at the answer, I also tried factorising but I cannot figure it out, I'm pretty sure that it has some factorization (perfect squares? not sure what they're called in english..)

Thank you in advanced, this forum is a very useful resource!

2. Jan 17, 2009

grief

So you said you tried dividing. That gives log ( (x2-1)2/((x+1)(x-1)2) ). Now you just need to use the fact that (x2-1)=(x-1)(x+1), and some things will cancel out.

3. Jan 17, 2009

rock.freak667

Note that x2-1=(x+1)(x-1)

Use some indices and you should get it.

4. Jan 17, 2009

nvez

The exact thing I needed!

Thank you guys, I can't appreciate this enough.