There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{10tan(\frac{0.9*3.14159x}{2})}{tan(\frac{0.9*3.14159}{2})}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{10tan(1.4137155x)}{tan(1.4137155)}\right)}{dx}\\=&\frac{10*-sec^{2}(1.4137155)(0)tan(1.4137155x)}{tan^{2}(1.4137155)} + \frac{10sec^{2}(1.4137155x)(1.4137155)}{tan(1.4137155)}\\=&\frac{14.137155sec^{2}(1.4137155x)}{tan(1.4137155)}\\ \end{split}\end{equation} \]

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