Răspuns :
[tex]\sqrt{7-4\sqrt3}=\sqrt{4+3-4\sqrt3}=\sqrt{(2-\sqrt3)^2}=|2-\sqrt3|=2-\sqrt3[/tex]
[tex]\it\sqrt{7-4\sqrt3} =\sqrt{4+3-4\sqrt3}=\sqrt{2^2-4\sqrt3 +(\sqrt3)^2}=
\\\;\\
\sqrt{(\it 2-\sqrt3)^2} =|\it 2-\sqrt3| = 2-\sqrt3\ .[/tex]