15-6/2-5 giúp tui với ạ

`(\sqrt{15}-\sqrt{6})/(\sqrt{2}-\sqrt{5})`

`=-(\sqrt{6}-\sqrt{15})/(\sqrt{2}-\sqrt{5})`

`=-(\sqrt{3}.(\sqrt{2}-\sqrt{5}))/(\sqrt{2}-\sqrt{5})`

`=-\sqrt{3}`

$#PDC$