There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{cos(x)}{e^{x}}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{cos(x)}{e^{x}}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{cos(x)}{e^{x}}\right)}{dx}\\=&\frac{-e^{x}cos(x)}{e^{{x}*{2}}} + \frac{-sin(x)}{e^{x}}\\=&\frac{-cos(x)}{e^{x}} - \frac{sin(x)}{e^{x}}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-cos(x)}{e^{x}} - \frac{sin(x)}{e^{x}}\right)}{dx}\\=&\frac{--e^{x}cos(x)}{e^{{x}*{2}}} - \frac{-sin(x)}{e^{x}} - \frac{-e^{x}sin(x)}{e^{{x}*{2}}} - \frac{cos(x)}{e^{x}}\\=&\frac{2sin(x)}{e^{x}}\\ \end{split}\end{equation} \]

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