Proposition: Natural Logarithm
The exponential function \(\exp:\mathbb R\to \mathbb R_{+}^*\) is invertible on any closed real interval \([a,b]\). Its inverse function is continuous, strictly monotonically increasing and called the natural logarithm
\[\ln:\mathbb R_{+}^*\to\mathbb R.\]
Table of Contents
Proofs: 1
 Proposition: Functional Equation of the Natural Logarithm
 Proposition: Derivative of the Natural Logarithm
 Proposition: Integral of the Natural Logarithm
Mentioned in:
Definitions: 1 2 3
Proofs: 4 5 6 7 8 9
Propositions: 10 11 12 13 14 15 16 17 18
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References
Bibliography
 Forster Otto: "Analysis 1, Differential und Integralrechnung einer Veränderlichen", Vieweg Studium, 1983