There are 1 questions in this calculation: for each question, the 1 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{-1}{t} - \frac{1}{(2{t}^{2})}\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{-1}{t} - \frac{\frac{1}{2}}{t^{2}}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{-1}{t} - \frac{\frac{1}{2}}{t^{2}}\right)}{dt}\\=&\frac{--1}{t^{2}} - \frac{\frac{1}{2}*-2}{t^{3}}\\=&\frac{1}{t^{2}} + \frac{1}{t^{3}}\\ \end{split}\end{equation} \]

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