Question

Simplifique :

4√63-√7

Answer 1

$4\sqrt{63}-\sqrt{7}=\\\\4\cdot\sqrt{9\cdot7}-\sqrt{7}=\\\\4\cdot\sqrt{9}\cdot\sqrt{7}-\srt{7}=\\\\4\cdot3\cdot\sqrt{7}-\sqrt{7}=\\\\12\cdot\sqrt{7}-\sqrt{7}=\\\\\boxed{11\sqrt{7}}$