There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ {(x + 1)}^{2} + {x}^{2} + {(1 + x)}^{2}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 3x^{2} + 4x + 2\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 3x^{2} + 4x + 2\right)}{dx}\\=&3*2x + 4 + 0\\=&6x + 4\\ \end{split}\end{equation} \]

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