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

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