Đáp án:
Lv2:
`A = \sqrt{(\sqrt{2}-1)^2} = |\sqrt{2}-1| = \sqrt{2}-1`
`B = \sqrt{(2-\sqrt{5})^2} = |2-\sqrt{5}| = \sqrt{5}-2`
`C = \sqrt{(3-\sqrt{11})^2} = |3-\sqrt{11}| = \sqrt{11}-3`
Lv2:
`A = \sqrt{(\sqrt{3}-2)^2} = |\sqrt{3}-2| = 2-\sqrt{3}`
`B = \sqrt{(1-\sqrt{5})^2} = |1-\sqrt{5}| = \sqrt{5}-1`
`C = \sqrt{(3-2\sqrt{2})^2} = |3-2\sqrt{2}| = 3-2\sqrt{2}`