Răspuns :

Impartim totul (si radicalii intre ei) si tinem cont de -/+
a. 3
b. -10rad3
c. -3rad2
d. 6rad3
e. 3rad3
f. 4

 

[tex]\displaystyle\bf\\a)~~\Big(9\sqrt{3}\Big):\Big(3\sqrt{3}\Big)=\frac{9\sqrt{3}}{3\sqrt{3}}=\frac{9}{3}=3\\\\\\b)~~\Big(30\sqrt{15}\Big):\Big(-3\sqrt{5}\Big)=\frac{30\sqrt{15}}{-3\sqrt{5}}=\frac{30\sqrt{3}\sqrt{5}}{-3\sqrt{5}}=\frac{30\sqrt{3}}{-3}=-10\sqrt{3}\\\\\\c)~~\Big(-12\sqrt{6}\Big):\Big(4\sqrt{3}\Big)=\frac{-12\sqrt{6}}{4\sqrt{3}} =\frac{-12\sqrt{2}\sqrt{3}}{4\sqrt{3}}=\frac{-12\sqrt{2}}{4}=-3\sqrt{2}[/tex]

.

[tex]\displaystyle\bf\\d)~~\Big(-27\sqrt{60}\Big):\Big(-9\sqrt{5}\Big)=\frac{27\sqrt{60}}{9\sqrt{5}} =\frac{27\times2\sqrt{3}\sqrt{5}}{9\sqrt{5}}=6\sqrt{3}\\\\\\e)~~\Big(27\sqrt{30}\Big):\Big(-9\sqrt{10}\Big)=\frac{27\sqrt{30}}{-9\sqrt{10}} =\frac{27\sqrt{3}\sqrt{10}}{-9\sqrt{10}}=\frac{27\sqrt{3}}{-9}=-3\sqrt{3}\\\\\\f)~~\Big(-10\sqrt{72}\Big):\Big(-5\sqrt{18}\Big)=\frac{-10\sqrt{72}}{-5\sqrt{18}} =\frac{10\sqrt{4}\sqrt{18}}{5\sqrt{18}}=\frac{10\times2}{5}=2\times2=4[/tex]