Đáp án+giải thích các bước giải:
B2:
a)
$\sqrt{(2\sqrt{2}-3)^2}$
$=|2\sqrt{2}-3|$
$=3-2\sqrt{2}$
b)
$\sqrt{(\dfrac{1}{\sqrt{2}}-\dfrac{1}{2})^2}$
$=|\dfrac{1}{\sqrt{2}}-\dfrac{1}{2}|$
$=\dfrac{1}{\sqrt{2}}-\dfrac{1}{2}$
$=\dfrac{\sqrt{2}-1}{2}$
c)
$\sqrt{(0,1-\sqrt{0,1})^2}$
$=|0,1-\sqrt{0,1}|$
$=\sqrt{0,1}-0,1$
B3:
a)
$\sqrt{(\sqrt{5}-\sqrt{2})^2} + \sqrt{(\sqrt{5}+\sqrt{2})^2}$
$=|\sqrt{5}-\sqrt{2}|+|\sqrt{5}+\sqrt{2}|$
$=\sqrt{5}-\sqrt{2}+\sqrt{5}+\sqrt{2}$
$=2\sqrt{5}$
b)
$\sqrt{(\sqrt{2}+1)^2}-\sqrt{(\sqrt{2}-5)^2}$
$=|\sqrt{2}+1|-|\sqrt{2}-5|$
$=\sqrt{2}+1-5+\sqrt{2}$
$=2\sqrt{2}-4$
