There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ 150sin(\frac{pix}{1000})\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 150sin(\frac{1}{1000}pix)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 150sin(\frac{1}{1000}pix)\right)}{dx}\\=&150cos(\frac{1}{1000}pix)*\frac{1}{1000}pi\\=&\frac{3picos(\frac{1}{1000}pix)}{20}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{3picos(\frac{1}{1000}pix)}{20}\right)}{dx}\\=&\frac{3pi*-sin(\frac{1}{1000}pix)*\frac{1}{1000}pi}{20}\\=&\frac{-3p^{2}i^{2}sin(\frac{1}{1000}pix)}{20000}\\ \end{split}\end{equation} \]

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