Question

Giúp mìng giải với^^

Answer 1

\(a,=\dfrac{\sqrt{10}\left(1+\sqrt{5}\right)}{\sqrt{5}+1}-3\sqrt{10}+\dfrac{12\left(4+\sqrt{10}\right)}{6}\\ =\sqrt{10}-3\sqrt{10}+8+2\sqrt{10}=8\\ d,D=\sqrt{\dfrac{6+2\sqrt{5}}{4}}-\sqrt{\dfrac{6-2\sqrt{5}}{4}}\\ D=\dfrac{\sqrt{5}+1}{2}-\dfrac{\sqrt{5}-1}{2}=\dfrac{2}{2}=1\)