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

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