Bài 1:
\(A=\dfrac{a+\sqrt{ab}-\sqrt{ab}+b-2\sqrt{ab}}{a-b}\cdot\left(\sqrt{a}+\sqrt{b}\right)\)
\(=\dfrac{\left(\sqrt{a}-\sqrt{b}\right)^2}{\sqrt{a}-\sqrt{b}}=\sqrt{a}-\sqrt{b}\)
Bài 2:
\(=6\sqrt{3}-6\sqrt{3}-\dfrac{1}{3}\sqrt{3}+\dfrac{7}{3}\sqrt{3}\)
\(=2\sqrt{3}\)
Đúng 2
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