# Thread: Solve c2 = c1(q2/q1)^x for x, assuming c1, c2, q1, q2 are known

1. ## Solve c2 = c1(q2/q1)^x for x, assuming c1, c2, q1, q2 are known

Hi guys, sorry been struggling with this for ages now and cant get close.

i want to find x in the following equation given all others are known.

c2 = c1(q2/q1)^x

Thanks

2. Originally Posted by pippo
… been struggling with this for ages …

c2 = c1(q2/q1)^x
What did you try?

I would isolate (q2/q1)^x, before using logarithms.

3. If you want to leave x by itself, just use log.

log(q2/q1) (c2/c1) = x

4. Originally Posted by pippo
c2 = c1(q2/q1)^x
u = c2, v = c1, w = q2/q1

u = v*w^x

w^x = u/v

That may make it clearer for you...