Quotient Rule for Derivatives/Examples/Exponential of x over x

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Example of Use of Quotient Rule for Derivatives

$\map {\dfrac \d {\d x} } {\dfrac {e^x} x} = \dfrac {e^x \paren {x - 1} } {x^2}$


Proof

\(\ds \map {\dfrac \d {\d x} } {\dfrac {e^x} x}\) \(=\) \(\ds \dfrac {x \map {\frac \d {\d x} } {e^x} - e^x \map {\frac \d {\d x} } x} {x^2}\) Quotient Rule for Derivatives
\(\ds \) \(=\) \(\ds \dfrac {x \cdot e^x - e^x \cdot 1} {x^2}\) Derivative of Exponential Function, Derivative of Identity Function
\(\ds \) \(=\) \(\ds \dfrac {e^x \paren {x - 1} } {x^2}\) simplification

$\blacksquare$


Sources