There are 1 questions in this calculation: for each question, the 1 derivative of U is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ U(6.0215 - 0.0695{e}^{(0.4U)})\ with\ respect\ to\ U：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - 0.0695U{e}^{(0.4U)} + 6.0215U\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - 0.0695U{e}^{(0.4U)} + 6.0215U\right)}{dU}\\=& - 0.0695{e}^{(0.4U)} - 0.0695U({e}^{(0.4U)}((0.4)ln(e) + \frac{(0.4U)(0)}{(e)})) + 6.0215\\=& - 0.0695{e}^{(0.4U)} - 0.0278U{e}^{(0.4U)} + 6.0215\\ \end{split}\end{equation} \]

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