Question

Question 5 (iv)
Rationalize the denominators of the following:

$\frac{1}{(\sqrt{7}-2)}$

Answer 1

Multiply and divide with $(\sqrt{7}+2).$
$\frac{1}{\sqrt{7}-2}=\frac{1(\sqrt{7}+2)}{(\sqrt{7}-2)(\sqrt{7}+2)}=\frac{\sqrt{7}+2}{(\sqrt{7}{)}^2-(2{)}^2}=\frac{\sqrt{7}+2}{7-4}=\frac{\sqrt{7}+2}{3}$