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

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