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

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