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

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