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

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