# The rationalisation factor of

Question:

The rationalisation factor of $\frac{1}{2 \sqrt{3}-\sqrt{5}}$ is

(a) $\sqrt{5}-2 \sqrt{3}$

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

(c) $(\sqrt{3}+\sqrt{5})$

(d) $\sqrt{12}+\sqrt{5}$

Solution:

Rationalisation factor of $\frac{1}{2 \sqrt{3}-\sqrt{5}}$ will be $2 \sqrt{3}+\sqrt{5}=\sqrt{4 \times 3}+\sqrt{5}=\sqrt{12}+\sqrt{5}$.

Hence, the correct answer is option (d).