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

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