There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ -0.25(x - y - 1)(x + 1)(y - 1)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -0.25yx^{2} + 0.25x^{2} - 0.25yx + 0.25x + 0.25y^{2}x - 0.25yx + 0.25yx - 0.25y + 0.25y^{2} - 0.25x + 0.25y - 0.25\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -0.25yx^{2} + 0.25x^{2} - 0.25yx + 0.25x + 0.25y^{2}x - 0.25yx + 0.25yx - 0.25y + 0.25y^{2} - 0.25x + 0.25y - 0.25\right)}{dx}\\=&-0.25y*2x + 0.25*2x - 0.25y + 0.25 + 0.25y^{2} - 0.25y + 0.25y + 0 + 0 - 0.25 + 0 + 0\\=&-0.5yx + 0.5x - 0.25y + 0.25y^{2} - 0.25y + 0.25y\\ \end{split}\end{equation} \]

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