There are 1 questions in this calculation: for each question, the 1 derivative of n is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ sqrt({(m - 3)}^{2} + {(n - 4)}^{2}) + z(3{m}^{2} + 4{n}^{2} - 12)\ with\ respect\ to\ n：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = sqrt(m^{2} - 6m + n^{2} - 8n + 25) + 3m^{2}z + 4zn^{2} - 12z\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( sqrt(m^{2} - 6m + n^{2} - 8n + 25) + 3m^{2}z + 4zn^{2} - 12z\right)}{dn}\\=&\frac{(0 + 0 + 2n - 8 + 0)*\frac{1}{2}}{(m^{2} - 6m + n^{2} - 8n + 25)^{\frac{1}{2}}} + 0 + 4z*2n + 0\\=&\frac{n}{(m^{2} - 6m + n^{2} - 8n + 25)^{\frac{1}{2}}} - \frac{4}{(m^{2} - 6m + n^{2} - 8n + 25)^{\frac{1}{2}}} + 8zn\\ \end{split}\end{equation} \]

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