đk: m ≠ 2
TH2 : m < 2 => 2-m > 0
\(3=\frac{9}{2\left|2-m\right|}\)
(=) \(3=\frac{9}{2\left(2-m\right)}\)
(=) 6(2-m) = 9
(=)2-m = 1,5
(=) m = 0,5
TH1 m > 2 => 2-m < 0
\(3=\frac{9}{-2\left(2-m\right)}\)
(=) -6(2-m) = 9
(=) 2-m = -1,5
(=) m = 3,5