Solving a Logarithm: Can't Remember How? Try Here!

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natgbz
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Can't remember how to do this (trying to solve for D):

x = b/D + a*log(D)

Any takers? Or is this impossible?
 
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Additive inverse of b/D;
Multiplicative inverse of 'a';

Not sure if the rest is impossible. I'm stuck, since D is the input of the logarithm function and it occurs as a factor too. Am I forgetting something simple, or is this beyond "intermediate" level algebra?
 
symbolipoint said:
Additive inverse of b/D;
Multiplicative inverse of 'a';

Not sure if the rest is impossible. I'm stuck, since D is the input of the logarithm function and it occurs as a factor too. Am I forgetting something simple, or is this beyond "intermediate" level algebra?


Maybe I can simplify the problem here:

a, b, and c are real numbers, D is greater than zero

c = b/D + a*log(D)

how does one solve for D?
 
HallsofIvy said:
One doesn't. Not in terms of elementary functions anyway. It might be possible to solve it in terms of the "Lambert W function".

How bout a Taylor Series expansion?