There are 1 questions in this calculation: for each question, the 4 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ sqrt(t)\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( sqrt(t)\right)}{dt}\\=&\frac{\frac{1}{2}}{(t)^{\frac{1}{2}}}\\=&\frac{1}{2t^{\frac{1}{2}}}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{1}{2t^{\frac{1}{2}}}\right)}{dt}\\=&\frac{\frac{-1}{2}}{2t^{\frac{3}{2}}}\\=&\frac{-1}{4t^{\frac{3}{2}}}\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( \frac{-1}{4t^{\frac{3}{2}}}\right)}{dt}\\=&\frac{-\frac{-3}{2}}{4t^{\frac{5}{2}}}\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( \frac{\frac{3}{8}}{t^{\frac{5}{2}}}\right)}{dt}\\=&\frac{\frac{3}{8}*\frac{-5}{2}}{t^{\frac{7}{2}}}\\=&\frac{-15}{16t^{\frac{7}{2}}}\\ \end{split}\end{equation} \]

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