Question

\(\sqrt{6+2\sqrt{5}}:\left(1+\sqrt{5}\right)\)

Answer 1

các bạn nào giỏi giúp mình với

Answer 2

\(\sqrt{6+2\sqrt{5}}:\left(1+\sqrt{5}\right)\)

\(=\sqrt{5+2\cdot\sqrt{5}+1}:\left(1+\sqrt{5}\right)\)

\(=\sqrt{\left(\sqrt{5}+1\right)^2}:\left(1+\sqrt{5}\right)\)

= \(\left(\sqrt{5}+1\right):\left(1+\sqrt{5}\right)=1\)

Answer 3

Ta có: \(\dfrac{\sqrt{6+2\sqrt{5}}}{1+\sqrt{5}}=\dfrac{\sqrt{1+5+2\sqrt{5}}}{1+\sqrt{5}}=\dfrac{\sqrt{\left(1+\sqrt{5}\right)^2}}{1+\sqrt{5}}=\dfrac{1+\sqrt{5}}{1+\sqrt{5}}=1\)