There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ lg(x) - sin(\frac{9πx}{20})\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( lg(x) - sin(\frac{9}{20}πx)\right)}{dx}\\=&\frac{1}{ln{10}(x)} - cos(\frac{9}{20}πx)*\frac{9}{20}π\\=&\frac{1}{xln{10}} - \frac{9πcos(\frac{9}{20}πx)}{20}\\ \end{split}\end{equation} \]

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