Help me solve this equation involving exponentials

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The discussion focuses on solving the equation involving exponentials: e^{1/z} + \frac{1}{1-e^{1/z}} = w, where z and w are complex numbers. The solution involves substituting u = e^{1/z}, transforming the equation into a quadratic form: u^2 - (1+w)u + (w-1) = 0. The quadratic formula is then applied to find u, followed by taking the logarithm to solve for z. The approach is validated by community input, confirming the correctness of the variable substitution and the application of the quadratic formula.

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I'm trying to solve the following equation for z\in \mathbb C \setminus \{ 0 \}, w\in \mathbb C:

<br /> e^{1/z} + \frac{1}{1-e^{1/z}} = w.<br />

How in the world should I go about doing that?
 
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Let u= e^{1/z}. Then your equation becomes
u+ \frac{1}{1- u}= w
Multiply both sides by 1- u to get u(1- u)+ 1= w(1- u) or u- u^2+ 1= w- uw which equivalent to the quadratic equation u^2- (1+w)u+ w-1= 0. Use the quadratic formula to solve that, then solve e^{1/z}= u[/math] by taking the logarithm of both sides.
 
HallsofIvy said:
Let u= e^{1/z}. Then your equation becomes
u+ \frac{1}{1- u}= w
Multiply both sides by 1- u to get u(1- u)+ 1= w(1- u) or u- u^2+ 1= w- uw which equivalent to the quadratic equation u^2- (1+w)u+ w-1= 0. Use the quadratic formula to solve that, then solve e^{1/z}= u[/math] by taking the logarithm of both sides.
<br /> <br /> Great. Thanks. This was my original approach, but for some reason I wasn&#039;t sure if I could make that change of variables and apply the quadratic formula like you did. But you&#039;ve confirmed my intuition, so I&#039;m going with it!
 
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