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

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