There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (x - 12)cos(x - 12) + 13\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( xcos(x - 12) - 12cos(x - 12) + 13\right)}{dx}\\=&cos(x - 12) + x*-sin(x - 12)(1 + 0) - 12*-sin(x - 12)(1 + 0) + 0\\=&cos(x - 12) - xsin(x - 12) + 12sin(x - 12)\\ \end{split}\end{equation} \]

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