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

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