There are 1 questions in this calculation: for each question, the 2 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{1}{2}ln(t - 2) - ln(t + 1) + ln(16)\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{1}{2}ln(t - 2) - ln(t + 1) + ln(16)\right)}{dt}\\=&\frac{\frac{1}{2}(1 + 0)}{(t - 2)} - \frac{(1 + 0)}{(t + 1)} + \frac{0}{(16)}\\=&\frac{1}{2(t - 2)} - \frac{1}{(t + 1)}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{1}{2(t - 2)} - \frac{1}{(t + 1)}\right)}{dt}\\=&\frac{(\frac{-(1 + 0)}{(t - 2)^{2}})}{2} - (\frac{-(1 + 0)}{(t + 1)^{2}})\\=&\frac{-1}{2(t - 2)^{2}} + \frac{1}{(t + 1)^{2}}\\ \end{split}\end{equation} \]

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