Question
========
What is the derivative of $f(x) = x^{7} e^{0.2 x}$, evaluated at $x = 0.9$?
Answerlist
----------
* $5.03$
* $6.08$
* $4.57$
* $6.62$
* $4.45$
Solution
========
Using the product rule we obtain
$$ f'(x) = e^{0.2 x} \cdot (7 \cdot x^6 + 0.2 x^7). $$
Evaluated at $x = 0.9$ and rounded to two digits the answer is
$f'(0.9) = 4.568278 = 4.57$.
Answerlist
----------
* False
* False
* True
* False
* False
Meta-information
================
extype: schoice
exsolution: 00100
exname: exp derivative