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

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