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

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