Bentuk sederhana dari 4 + akar 5 per 2 + akar 5 adalah...

[tex]\displaystyle \frac{4+\sqrt{5}}{2+\sqrt{5}}=\frac{4+\sqrt{5}}{\sqrt{5}+2} \\ \frac{4+\sqrt{5}}{\sqrt{5}+2}\times \frac{\sqrt{5}-2}{\sqrt{5}-2}=\frac{(4+\sqrt{5})(\sqrt{5}-2)}{5-2^2} \\ \frac{4\sqrt{5}-8+5-2\sqrt{5}}{1}=4\sqrt{5}-8+5-2\sqrt{5}=-3+2\sqrt{5}=2\sqrt{5}-3[/tex]