There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ arccos(5x) + bsin(5x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( arccos(5x) + bsin(5x)\right)}{dx}\\=&(\frac{-(5)}{((1 - (5x)^{2})^{\frac{1}{2}})}) + bcos(5x)*5\\=&\frac{-5}{(-25x^{2} + 1)^{\frac{1}{2}}} + 5bcos(5x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-5}{(-25x^{2} + 1)^{\frac{1}{2}}} + 5bcos(5x)\right)}{dx}\\=&-5(\frac{\frac{-1}{2}(-25*2x + 0)}{(-25x^{2} + 1)^{\frac{3}{2}}}) + 5b*-sin(5x)*5\\=&\frac{-125x}{(-25x^{2} + 1)^{\frac{3}{2}}} - 25bsin(5x)\\ \end{split}\end{equation} \]

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