# Homework Help: Find x

1. Sep 22, 2008

### rise

how can u solve this equation (3^x)-(3^-x)=4...hehe:P
please i really need it fast..TT

Last edited: Sep 22, 2008
2. Sep 22, 2008

"please i really need it fast."

That's not how it works - you need to show some of your first tries, or explain what you've done that hasn't worked. At that time you may receive hints.

3. Sep 22, 2008

### razored

Hmm.. to get you started, multiply everything by 3^(x).. from there everything is bright and clear.

4. Sep 23, 2008

### sutupidmath

then take a substitution of the form $$t=3^x$$ so u'll get a quadratic eq.

5. Sep 23, 2008

### Mentallic

once you get you solve the quadratic, don't forget to substitute 3x=t back again

6. Sep 23, 2008

### dirk_mec1

Guys we've helped enough now let the OP do the math.

7. Sep 24, 2008

### rise

damn!!you people are damn good!:P i tried many times but nothing happens..THX GUYS:)