There are 1 questions in this calculation: for each question, the 4 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ Xt + \frac{v{t}^{2}}{2} + \frac{a{t}^{3}}{6}\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = Xt + \frac{1}{2}vt^{2} + \frac{1}{6}at^{3}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( Xt + \frac{1}{2}vt^{2} + \frac{1}{6}at^{3}\right)}{dt}\\=&X + \frac{1}{2}v*2t + \frac{1}{6}a*3t^{2}\\=&X + vt + \frac{at^{2}}{2}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( X + vt + \frac{at^{2}}{2}\right)}{dt}\\=&0 + v + \frac{a*2t}{2}\\=&v + at\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( v + at\right)}{dt}\\=&0 + a\\=&a\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( a\right)}{dt}\\=&0\\ \end{split}\end{equation} \]

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