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

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