Question

Giá trị rút gọn của biểu thức  là...

Answer 1

\(\left(\sqrt{8+3\sqrt{7}+\sqrt{8-3\sqrt{7}}}\right)^2\)

=\(8+3\sqrt{7}+8-3\sqrt{7}+2\sqrt{64-63}\)

=16+2=18

Answer 2

\(\left(\sqrt{8+3\sqrt{7}}+\sqrt{8-3\sqrt{7}}\right)^2=16+2\sqrt{8^2-\left(3\sqrt{7}\right)^2}=16+2=18\)

Answer 3

\(\left(\sqrt{8+3\sqrt{7}}+\sqrt{8-3\sqrt{7}}\right)^2\)

\(=8+3\sqrt{7}+2\sqrt{\left(8+3\sqrt{7}\right)\left(8-3\sqrt{7}\right)}+8-3\sqrt{7}\)

\(=16\cdot\sqrt{8^2-\left(3\sqrt{7}\right)^2}=16\cdot1=16\)