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

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