Derivative of Exponential of Function

Theorem

Let $u$ be a differentiable real function of $x$.

Let $e^u$ be the exponential function of $u$.

Then:

$\map {\dfrac \d {\d x} } {e^u} = e^u \dfrac {\d u} {\d x}$


Proof

\(\ds \map {\frac \d {\d x} } {e^u}\) \(=\) \(\ds \map {\frac \d {\d u} } {e^u} \frac {\d u} {\d x}\) Chain Rule for Derivatives
\(\ds \) \(=\) \(\ds e^u \frac {\d u} {\d x}\) Derivative of Exponential Function

$\blacksquare$


Sources

  • 1968: Murray R. Spiegel: Mathematical Handbook of Formulas and Tables ... (previous) ... (next): $\S 13$: Derivatives of Exponential and Logarithmic Functions: $13.29$
  • 1974: Murray R. Spiegel: Theory and Problems of Advanced Calculus (SI ed.) ... (previous) ... (next): Chapter $4$. Derivatives: Derivatives of Special Functions: $12$