\(\sqrt{7-4\sqrt{3}}+\sqrt{12+6\sqrt{3}}\)
\(=\sqrt{2^2-2.2.\sqrt{3}+\sqrt{3^2}}+\sqrt{3^2+2.3.\sqrt{3}+\sqrt{3^2}}\)
\(=\sqrt{\left(2-\sqrt{3}\right)^2}+\sqrt{\left(3+\sqrt{3}\right)^2}\)
\(=\left|2-\sqrt{3}\right|+\left|3+\sqrt{3}\right|\)
\(=2-\sqrt{3}+3+\sqrt{3}\)
\(=5\)