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

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