Question

tính

\(\sqrt{9+4\sqrt{2}}+\sqrt{9-4\sqrt{2}}\)

Answer 1

\(\sqrt{9+4\sqrt{2}}+\sqrt{9-4\sqrt{2}}=\sqrt{\left(\sqrt{8}+1\right)^2}+\sqrt{\left(\sqrt{8}-1\right)^2}=\sqrt{8}+1+\sqrt{8}-1=2\sqrt{8}=4\sqrt{2}\)

Answer 2

Answer 3

\(\sqrt{9+4\sqrt{2}}+\sqrt{9-4\sqrt{2}}\)

=\(\sqrt{8+4\sqrt{2}+1}+\sqrt{8-4\sqrt{2}+1}\)

\(=\sqrt{\left(\sqrt{8}+1\right)^2}+\sqrt{\left(\sqrt{8}-1\right)^2}\)

\(=\sqrt{8}+1+\sqrt{8}-1\)

\(=2\sqrt{8}\)