a: \(M=\dfrac{x}{x-3}:\dfrac{x-2\left(x-3\right)}{x\left(x-3\right)}\)
\(=\dfrac{x}{x-3}\cdot\dfrac{x\left(x-3\right)}{x-2x+6}=\dfrac{x^2}{-x+6}\)
b: x^2-2x=0
=>x=0(loại) hoặc x=2(nhận)
Khi x=2 thì \(M=\dfrac{2^2}{-2+6}=\dfrac{4}{4}=1\)
c: M>=0
=>-x+6>0
=>-x>-6
=>x<6


