第116页

信息发布者:
C
C
​$ 9+4\sqrt {5}$​
​$ \sqrt {5}$​
解:原式​$=(\sqrt {3})²-2²$​
​$=3-4$​
​$=-1$​
解:原式​$=(\sqrt {2})²-2×\sqrt {2}×\sqrt {3}+(\sqrt {3})²+6\sqrt {\frac {1}{3}×2}$​
​$=5-2\sqrt {6}+2\sqrt {6}$​
​$=5$​
解:原式​$=\frac {6×(\sqrt {7}+1)}{6}+\frac {6×(\sqrt {7}-1)}{6}$​
​$=\sqrt {7}+1+\sqrt {7}-1$​
​$=2\sqrt {7}$​
解:原式​$=a+b+2\sqrt {ab}-a-b+2\sqrt {ab}$​
​$=4\sqrt {ab}$​