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Are there rational $a$ and $b$ with $$a+be = \frac{1}{\ln 2}\ ?$$

I used the absence of rational solutions repeatedly in this answer.

Here is a proof using Schanuel's conjecture: $e^q$ is transcendental for any algebraic $q$ by the Lindemann-Weierstrass theorem. In particular $e^q\neq 2$ and $\ln 2$ is irrational. So $1$ and $\ln 2$ are linearly independent over the rationals. Then by Schanuel's conjecture, the set $\{1, \ln 2, e, 2\}$ must have transcendence degree at least $2$ over the rationals, while the above equation would imply that the transcendence degree is only $1$. So there are no rational solutions to the above equation.

Is there a proof without that conjecture?

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    $\begingroup$ "$e^q$ is transcendental for any algebraic $q$" – well, except $q=0$. $\endgroup$ Commented Sep 8, 2022 at 6:20

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