There are 1 questions in this calculation: for each question, the 1 derivative of I is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ UI - {I}^{2}r\ with\ respect\ to\ I：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = UI - rI^{2}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( UI - rI^{2}\right)}{dI}\\=&U - r*2I\\=&U - 2rI\\ \end{split}\end{equation} \]

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