d. \(\left(\sqrt{3-\sqrt{5}}+\sqrt{3+\sqrt{5}}\right)^2\)
= \(\left(\sqrt{3-\sqrt{5}}\right)^2+2.\sqrt{3-\sqrt{5}}.\sqrt{3+\sqrt{5}}+\left(\sqrt{3+\sqrt{5}}\right)^2\)
= \(\sqrt{3-\sqrt{5}}+2\left[\left(\sqrt{3-\sqrt{5}}\right)^2-\left(\sqrt{3+\sqrt{5}}\right)^2\right]+\sqrt{3+\sqrt{5}}\)
= \(\sqrt{3-\sqrt{5}}+2\left(3-\sqrt{5}-3-\sqrt{5}\right)+\sqrt{3+\sqrt{5}}\)
= \(\sqrt{3-\sqrt{5}}+\sqrt{3+\sqrt{5}}+\left(-4\sqrt{5}\right)\)
= -7,196
e: ta có: \(\left(\sqrt{4-\sqrt{7}}-\sqrt{4+\sqrt{7}}\right)^2+2\sqrt{7}\)
\(=4-\sqrt{7}+4+\sqrt{7}-2\cdot\sqrt{16-7}+2\sqrt{7}\)
\(=8-2\cdot3+2\sqrt{7}\)
\(=2\sqrt{7}+2\)
