There are 1 questions in this calculation: for each question, the 3 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ third\ derivative\ of\ function\ sin(x) - cos(2)xsqrt(x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = sin(x) - xcos(2)sqrt(x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( sin(x) - xcos(2)sqrt(x)\right)}{dx}\\=&cos(x) - cos(2)sqrt(x) - x*-sin(2)*0sqrt(x) - \frac{xcos(2)*\frac{1}{2}}{(x)^{\frac{1}{2}}}\\=& - cos(2)sqrt(x) + cos(x) - \frac{x^{\frac{1}{2}}cos(2)}{2}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( - cos(2)sqrt(x) + cos(x) - \frac{x^{\frac{1}{2}}cos(2)}{2}\right)}{dx}\\=& - -sin(2)*0sqrt(x) - \frac{cos(2)*\frac{1}{2}}{(x)^{\frac{1}{2}}} + -sin(x) - \frac{\frac{1}{2}cos(2)}{2x^{\frac{1}{2}}} - \frac{x^{\frac{1}{2}}*-sin(2)*0}{2}\\=& - \frac{3cos(2)}{4x^{\frac{1}{2}}} - sin(x)\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( - \frac{3cos(2)}{4x^{\frac{1}{2}}} - sin(x)\right)}{dx}\\=& - \frac{3*\frac{-1}{2}cos(2)}{4x^{\frac{3}{2}}} - \frac{3*-sin(2)*0}{4x^{\frac{1}{2}}} - cos(x)\\=&\frac{3cos(2)}{8x^{\frac{3}{2}}} - cos(x)\\ \end{split}\end{equation} \]

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