There are 1 questions in this calculation: for each question, the 1 derivative of b is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ -0.25*0.2{(\frac{0.0434}{(0.25 - b)})}^{2}*0.2\ with\ respect\ to\ b：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{-0.0000188356}{(-b + 0.25)(-b + 0.25)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{-0.0000188356}{(-b + 0.25)(-b + 0.25)}\right)}{db}\\=&\frac{-0.0000188356(\frac{-(-1 + 0)}{(-b + 0.25)^{2}})}{(-b + 0.25)} - \frac{0.0000188356(\frac{-(-1 + 0)}{(-b + 0.25)^{2}})}{(-b + 0.25)}\\=&\frac{-0.0000188356}{(-b + 0.25)(-b + 0.25)(-b + 0.25)} - \frac{0.0000188356}{(-b + 0.25)(-b + 0.25)(-b + 0.25)}\\ \end{split}\end{equation} \]

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