There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ x{2}^{(9 - x)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = x{2}^{(-x + 9)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( x{2}^{(-x + 9)}\right)}{dx}\\=&{2}^{(-x + 9)} + x({2}^{(-x + 9)}((-1 + 0)ln(2) + \frac{(-x + 9)(0)}{(2)}))\\=&{2}^{(-x + 9)} - x{2}^{(-x + 9)}ln(2)\\ \end{split}\end{equation} \]

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