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

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