Respostas

2014-04-24T19:53:22-03:00
\frac{3}{ \sqrt{2}+ \sqrt{5}} = \frac{3}{ \sqrt{2}+ \sqrt{5}} \cdot \frac{ \sqrt{2}- \sqrt{5}}{ \sqrt{2}- \sqrt{5}} =\frac{ 3(\sqrt{2}- \sqrt{5})}{ (\sqrt{2})^2- (\sqrt{5})^2} =\frac{ 3(\sqrt{2}- \sqrt{5})}{2-5}=\frac{ 3(\sqrt{2}- \sqrt{5})}{-3}\\ \\=\frac{ 3(\sqrt{2}- \sqrt{5})}{-3}= -(\sqrt{2}- \sqrt{5})=-\sqrt{2}+ \sqrt{5}=\sqrt{5}- \sqrt{2}
os codigos nao se tornaram numeros
Sim!