There are 1 questions in this calculation: for each question, the 1 derivative of l is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(35l + 8{l}^{2} - {l}^{3})}{l}\ with\ respect\ to\ l：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 8l - l^{2} + 35\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 8l - l^{2} + 35\right)}{dl}\\=&8 - 2l + 0\\=& - 2l + 8\\ \end{split}\end{equation} \]

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