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Is it possible to simplify $W(x\cdot e^{a+x})$?

Because $W(x\cdot e^{x})=x$

So I was wondering if it was possible to simplify this expression.

Idrees Samim
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  • Assuming $a$ is real, this would be the same as simplifying $W(cxe^x)$ for $c>0$ (I cannot think of anything helpful for this case) – parsiad Aug 19 '15 at 18:20
  • Really? Is it impossible to find a method to remove the lambert w term? In any case? – Idrees Samim Aug 19 '15 at 18:25
  • I dont think that there will be a simplification. Because there is a linear scaling factor $k=e^a$ which shifts the value of the function, again as Lambert-$W$. This is basically true for any shifting. Especially, $W$ is non-linear and one cannot separate it. But, one can approximate it and find some approximate simplifications. See the answer. – Seyhmus Güngören Aug 02 '17 at 23:52

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I'd have to say no, this is not simplify-able.

You can however attempt to obtain an expansion via logarithms:

$$W(x)=\ln(x)-\ln(\ln(x))+\mathcal O(\ln(\ln(\ln(x))))$$

So,

$$W(xe^{a+x})=a+x+\ln(x)-\ln(a+x+\ln(x))+\mathcal O(\ln(\ln(x)))$$

as $x\to\infty$.