第29页

信息发布者:
$\frac{1}{2}$
$\frac{\sqrt{2}}{2}$
$\frac{\sqrt{3}}{2}$
$\frac{\sqrt{3}}{2}$
$\frac{\sqrt{2}}{2}$
$\frac{1}{2}$
$\frac{\sqrt{3}}{3}$
1
$\sqrt{3}$
根式
大小
$30^\circ$
C
C
1
$\frac{6}{5}\sqrt{3}$
解:原式​$=\frac {1}{2} ×(\frac {\sqrt {2}}{2})^2 - \sqrt {3} $​
​$= \frac {1}{2} ×\frac {1}{2} - \sqrt {3} $​
​$= \frac {1}{4} - \sqrt {3}$​
解:原式​$=\frac {\sqrt {2}}{2} - \sqrt {3} ×\frac {\sqrt {3}}{3} - \frac {2}{3} ×(\frac {\sqrt {3}}{2})^2 $​
​$= \frac {\sqrt {2}}{2} - 1 - \frac {2}{3} ×\frac {3}{4} $​
​$= \frac {\sqrt {2}}{2} - 1 - \frac {1}{2} $​
​$= \frac {\sqrt {2} - 3}{2}$​