Natural Logs and inverse functions

b200w
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Homework Statement


Find the inverse equation (i.e. solve for x)
y=(e^x)/(1+2e^x)2. The attempt at a solution
e^x = y(1+2e^x)
x = ln(y) + ln(1+2e^x)
?
Profit!

I can't figure out what to do with ln(1+2e^x) to get the x out of there so I can finish isolating x. I tried balancing it another way and ended up with x = ln(e^x - y) - ln(2y) which as far as I can tell is worse. Any suggestions? As far as I can tell I'm probably just missing something obvious but I've been sitting here for a while trying to figure it out...
 
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Starting with y = e^x/(1 + 2e^x),
multiply both sides by (1 + 2e^x).

Get all the terms that involve e^x on one side, and all other terms on the other side.
Factor e^x out of the terms that have this factor and divide both sides by the factor that isn't e^x.
 
*facepalm* Thank you... I don't know why I couldn't figure that out...
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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