There are 1 questions in this calculation: for each question, the 1 derivative of a is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ -alog_{2}^{a} - blog_{2}^{b} - clog_{2}^{c} + l(a + b + c - 1)\ with\ respect\ to\ a：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -alog_{2}^{a} - blog_{2}^{b} - clog_{2}^{c} + la + bl + cl - l\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -alog_{2}^{a} - blog_{2}^{b} - clog_{2}^{c} + la + bl + cl - l\right)}{da}\\=&-log_{2}^{a} - a(\frac{(\frac{(1)}{(a)} - \frac{(0)log_{2}^{a}}{(2)})}{(ln(2))}) - b(\frac{(\frac{(0)}{(b)} - \frac{(0)log_{2}^{b}}{(2)})}{(ln(2))}) - c(\frac{(\frac{(0)}{(c)} - \frac{(0)log_{2}^{c}}{(2)})}{(ln(2))}) + l + 0 + 0 + 0\\=&-log_{2}^{a} - \frac{1}{ln(2)} + l\\ \end{split}\end{equation} \]

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