There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (x - 50)(\frac{300}{(x - 50)} + 240 - 4x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{300x}{(x - 50)} - 4x^{2} + 440x - \frac{15000}{(x - 50)} - 12000\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{300x}{(x - 50)} - 4x^{2} + 440x - \frac{15000}{(x - 50)} - 12000\right)}{dx}\\=&300(\frac{-(1 + 0)}{(x - 50)^{2}})x + \frac{300}{(x - 50)} - 4*2x + 440 - 15000(\frac{-(1 + 0)}{(x - 50)^{2}}) + 0\\=&\frac{-300x}{(x - 50)^{2}} + \frac{15000}{(x - 50)^{2}} - 8x + \frac{300}{(x - 50)} + 440\\ \end{split}\end{equation} \]

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