There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ k(5(sqrt(400) + {x}^{2}) + 3(100 - x))\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 5ksqrt(400) + 5kx^{2} - 3kx + 300k\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 5ksqrt(400) + 5kx^{2} - 3kx + 300k\right)}{dx}\\=&5k*0*\frac{1}{2}*400^{\frac{1}{2}} + 5k*2x - 3k + 0\\=&10kx - 3k\\ \end{split}\end{equation} \]

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