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

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