There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ xsin(\frac{1}{2}) + 3Xsin(\frac{7}{10})\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( xsin(\frac{1}{2}) + 3Xsin(\frac{7}{10})\right)}{dx}\\=&sin(\frac{1}{2}) + xcos(\frac{1}{2})*0 + 3Xcos(\frac{7}{10})*0\\=&sin(\frac{1}{2})\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( sin(\frac{1}{2})\right)}{dx}\\=&cos(\frac{1}{2})*0\\ \end{split}\end{equation} \]

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