There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ -x + \frac{4}{(-k - {({k}^{2} + 8)}^{\frac{1}{2}})}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -x + \frac{4}{(-k - (k^{2} + 8)^{\frac{1}{2}})}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -x + \frac{4}{(-k - (k^{2} + 8)^{\frac{1}{2}})}\right)}{dx}\\=&-1 + 4(\frac{-(0 - (\frac{\frac{1}{2}(0 + 0)}{(k^{2} + 8)^{\frac{1}{2}}}))}{(-k - (k^{2} + 8)^{\frac{1}{2}})^{2}})\\=&-1\\ \end{split}\end{equation} \]

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