\(a.\dfrac{2-\sqrt{2}}{\sqrt{2}}=\dfrac{\sqrt{2}\left(\sqrt{2}-1\right)}{\sqrt{2}}=\sqrt{2}-1\)
\(b.B=\dfrac{\sqrt{x^2-6x+9}}{6-2x}=\dfrac{\text{ |}x-3\text{ |}}{-2\left(x-3\right)}\)
+) \(B=\dfrac{1}{-2}\left(x>3\right)\)
+) \(B=\dfrac{1}{2}\left(x< 3\right)\)