There are 1 questions in this calculation: for each question, the 1 derivative of s is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{ksxI}{(ks + s)(1 + \frac{z}{s})}\ with\ respect\ to\ s：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{kxIs}{(ks + s)(\frac{z}{s} + 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{kxIs}{(ks + s)(\frac{z}{s} + 1)}\right)}{ds}\\=&\frac{(\frac{-(k + 1)}{(ks + s)^{2}})kxIs}{(\frac{z}{s} + 1)} + \frac{(\frac{-(\frac{z*-1}{s^{2}} + 0)}{(\frac{z}{s} + 1)^{2}})kxIs}{(ks + s)} + \frac{kxI}{(ks + s)(\frac{z}{s} + 1)}\\=&\frac{-k^{2}xIs}{(ks + s)^{2}(\frac{z}{s} + 1)} - \frac{kxIs}{(ks + s)^{2}(\frac{z}{s} + 1)} + \frac{kxzI}{(ks + s)(\frac{z}{s} + 1)^{2}s} + \frac{kxI}{(ks + s)(\frac{z}{s} + 1)}\\ \end{split}\end{equation} \]

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