Simplify the radical expression by rationalizing the denominator. Use the notation sqrt if a square root is in your answer. This question is 4 / sqrt(21)

Answer 1

To rationalize the denominator of the expression \( \frac{4}{\sqrt{21}} \), we can multiply both the numerator and the denominator by \( \sqrt{21} \):

\[ \frac{4}{\sqrt{21}} \cdot \frac{\sqrt{21}}{\sqrt{21}} = \frac{4\sqrt{21}}{21} \]

Thus, the simplified expression is:

\[ \frac{4\sqrt{21}}{21} \]