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

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