There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(x + 18)}{({10}^{t})}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = x{10}^{(-t)} + 18 * {10}^{(-t)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( x{10}^{(-t)} + 18 * {10}^{(-t)}\right)}{dx}\\=&{10}^{(-t)} + x({10}^{(-t)}((0)ln(10) + \frac{(-t)(0)}{(10)})) + 18({10}^{(-t)}((0)ln(10) + \frac{(-t)(0)}{(10)}))\\=&{10}^{(-t)}\\ \end{split}\end{equation} \]

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