There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{x}{6} + x\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{7}{6}x\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{7}{6}x\right)}{dx}\\=&\frac{7}{6}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{7}{6}\right)}{dx}\\=&0\\ \end{split}\end{equation} \]

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