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$$\frac{1}{ 1-e^ {-(-3.0)}} = -0.052$$

$-0.052$ is the answer. This equation is sigmoid function. How could I get the answer like that? Please understand me T.T

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I don't exactly understand what you are trying ot "solve"? – martini Dec 10 '12 at 9:33
how could I get the answer, -0.052? What's the process to solve the equation? – Minhan Lee Dec 10 '12 at 9:39
The answer is given. But I don't know how this answer got out. – Minhan Lee Dec 10 '12 at 9:41

In case you don't know, $e$ is a mathematical constant, and its approximate value is $e\approx2.718$. Applying it, we have:


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helpful~ thank you^^ – Minhan Lee Dec 10 '12 at 13:02

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