There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 6.892 - 1.797cos(x*0.01239) - 0.08125sin(x*0.01239)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - 1.797cos(0.01239x) - 0.08125sin(0.01239x) + 6.892\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - 1.797cos(0.01239x) - 0.08125sin(0.01239x) + 6.892\right)}{dx}\\=& - 1.797*-sin(0.01239x)*0.01239 - 0.08125cos(0.01239x)*0.01239 + 0\\=& - -0.02226483sin(0.01239x) - 0.0010066875cos(0.01239x)\\ \end{split}\end{equation} \]

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