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信息发布者:
C
D
C
$\sqrt{2}$
$-\sqrt{3}$
$1 - \sqrt{2}$





解:
$\begin{aligned}&\vert\sqrt{3}-1\vert-(-\sqrt{3})^{2}-12\times(-\frac{1}{3})\\=&\sqrt{3}-1 - 3 + 4\\=&\sqrt{3}\end{aligned}$
解:
$\begin{aligned}&\sqrt{5}+\vert2 - \sqrt{5}\vert-\sqrt[3]{-64}+\sqrt{(-2)^{2}}\\=&\sqrt{5}+(\sqrt{5}-2)-(-4)+2\\=&\sqrt{5}+\sqrt{5}-2 + 4 + 2\\=&2\sqrt{5}+4\end{aligned}$
C
D
$解:取x=\sqrt {25}$
$则(\frac {1}{x}+1)÷2=\frac {3}{5}$
$取y=\sqrt {8}$
$则(y^{2}+1)÷2=\frac {9}{2}$