There are 1 questions in this calculation: for each question, the 4 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ ln(5 + 4x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = ln(4x + 5)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( ln(4x + 5)\right)}{dx}\\=&\frac{(4 + 0)}{(4x + 5)}\\=&\frac{4}{(4x + 5)}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{4}{(4x + 5)}\right)}{dx}\\=&4(\frac{-(4 + 0)}{(4x + 5)^{2}})\\=&\frac{-16}{(4x + 5)^{2}}\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( \frac{-16}{(4x + 5)^{2}}\right)}{dx}\\=&-16(\frac{-2(4 + 0)}{(4x + 5)^{3}})\\=&\frac{128}{(4x + 5)^{3}}\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( \frac{128}{(4x + 5)^{3}}\right)}{dx}\\=&128(\frac{-3(4 + 0)}{(4x + 5)^{4}})\\=&\frac{-1536}{(4x + 5)^{4}}\\ \end{split}\end{equation} \]

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