[tex]\texttt{Descompunem in factori primi, numarul 756} \\ \\
756 = 2^2 \times 3^3 \times 7 \\ \\
\sqrt{756} = \sqrt{2^2 \times 3^3 \times 7 } = \\ \\
= \sqrt{2^2 \times 3^2 \times 3 \times 7 } = 2 \times 3\times \sqrt{ 3 \times 7 } = \boxed{6\sqrt{21 } } [/tex]
