Simplify each of the following by rationalizing the denominator:

(i) \(\frac{1}{\sqrt{6}}\)

(ii) [tex]\(\frac{1}{\sqrt{5} + \sqrt{2}}\)[/tex]



Answer :

Sure, let's simplify each of the given expressions by rationalizing their denominators.

### Part (i) Rationalizing the denominator of \( \frac{1}{\sqrt{6}} \)

To rationalize the denominator of the expression \( \frac{1}{\sqrt{6}} \), we need to eliminate the square root from the denominator. We do this by multiplying both the numerator and the denominator by \( \sqrt{6} \).

[tex]\[ \frac{1}{\sqrt{6}} \cdot \frac{\sqrt{6}}{\sqrt{6}} = \frac{\sqrt{6}}{6} \][/tex]

So the simplified form is:

[tex]\[ \frac{\sqrt{6}}{6} \approx 0.4082 \][/tex]

### Part (ii) Rationalizing the denominator of \( \frac{1}{\sqrt{5} + \sqrt{2}} \)

To rationalize the denominator of \( \frac{1}{\sqrt{5} + \sqrt{2}} \), we multiply the numerator and the denominator by the conjugate of the denominator, which is \( \sqrt{5} - \sqrt{2} \).

[tex]\[ \frac{1}{\sqrt{5} + \sqrt{2}} \cdot \frac{\sqrt{5} - \sqrt{2}}{\sqrt{5} - \sqrt{2}} = \frac{\sqrt{5} - \sqrt{2}}{(\sqrt{5} + \sqrt{2})(\sqrt{5} - \sqrt{2})} \][/tex]

In the denominator, we use the difference of squares formula \( a^2 - b^2 \):

[tex]\[ (\sqrt{5})^2 - (\sqrt{2})^2 = 5 - 2 = 3 \][/tex]

Thus, the expression simplifies to:

[tex]\[ \frac{\sqrt{5} - \sqrt{2}}{3} \][/tex]

And approximately:

[tex]\[ \frac{\sqrt{5} - \sqrt{2}}{3} \approx 0.2740 \][/tex]

To summarize:

1. \( \frac{1}{\sqrt{6}} \) simplifies to \( \frac{\sqrt{6}}{6} \approx 0.4082 \).
2. \( \frac{1}{\sqrt{5} + \sqrt{2}} \) simplifies to \( \frac{\sqrt{5} - \sqrt{2}}{3} \approx 0.2740 \).

These are the simplified forms of the given expressions with their denominators rationalized.