rút gọn biểu thức $\dfrac{\sqrt{2}+1}{\sqrt{4-2\sqrt{3}}}$ : $\dfrac{\sqrt{3}+1}{\sqrt{2}-1}$

$\dfrac{\sqrt 2+1}{\sqrt{4-2\sqrt 3}}:\dfrac{\sqrt 3+1}{\sqrt 2-1}\\=\dfrac{\sqrt 2+1}{\sqrt{3-2\sqrt 3+1}}.\dfrac{\sqrt 2-1}{\sqrt 3+1}\\=\dfrac{\sqrt 2+1}{\sqrt{(\sqrt 3-1)^2}}.\dfrac{\sqrt 2-1}{\sqrt 3+1}\\=\dfrac{(\sqrt 2+1)(\sqrt 2-1)}{|\sqrt 3-1|(\sqrt 3+1)}\\=\dfrac{2-1}{(\sqrt 3-1)(\sqrt 3+1)}\\=\dfrac{1}{2}$