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

Your problem has not been solved here? Please take a look at the  hot problems ！