There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 0.25(3.2 - x)(4.2 - x)x\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 3.36x - 0.8x^{2} - 1.05x^{2} + 0.25x^{3}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 3.36x - 0.8x^{2} - 1.05x^{2} + 0.25x^{3}\right)}{dx}\\=&3.36 - 0.8*2x - 1.05*2x + 0.25*3x^{2}\\=& - 1.6x - 2.1x + 0.75x^{2} + 3.36\\ \end{split}\end{equation} \]

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