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

Your problem has not been solved here? Please take a look at the  hot problems ！