There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(-0.04{x}^{2} + 1.85x + 1.4)}{(x + 1)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{-0.04x^{2}}{(x + 1)} + \frac{1.85x}{(x + 1)} + \frac{1.4}{(x + 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{-0.04x^{2}}{(x + 1)} + \frac{1.85x}{(x + 1)} + \frac{1.4}{(x + 1)}\right)}{dx}\\=&-0.04(\frac{-(1 + 0)}{(x + 1)^{2}})x^{2} - \frac{0.04*2x}{(x + 1)} + 1.85(\frac{-(1 + 0)}{(x + 1)^{2}})x + \frac{1.85}{(x + 1)} + 1.4(\frac{-(1 + 0)}{(x + 1)^{2}})\\=&\frac{0.04x^{2}}{(x + 1)(x + 1)} - \frac{0.08x}{(x + 1)} - \frac{1.85x}{(x + 1)(x + 1)} - \frac{1.4}{(x + 1)(x + 1)} + \frac{1.85}{(x + 1)}\\ \end{split}\end{equation} \]

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