For the given figure length of OA is :

1. $\sqrt{5}$

2. $\sqrt{3}$

3. $\sqrt{5} \text{ or } \sqrt{3}$

4. neither $\sqrt{5}$ nor $\sqrt{3}$

$2\sqrt{3} \times 3\sqrt{8}$ is :

1. rational

2. irrational

3. neither rational nor irrational

4. 12 $\times \sqrt{5}$

State whether the following numbers are rational or not :

(i) $(2 + \sqrt{2})^2$

(ii) $(3 - \sqrt{3})^2$

(iii) $(5 + \sqrt{5})(5 - \sqrt{5})$

(iv) $(\sqrt{3} - \sqrt{2})^2$

Find the square of :

(i) $\dfrac{3\sqrt{5}}{5}$

(ii) $\sqrt{3} + \sqrt{2}$

(iii) $\sqrt{5} - 2$

(iv) $3 + 2\sqrt{5}$