(18.) \( \frac{\sqrt{6}}{\sqrt{2 n}} \)

Did you know that simplifying square roots can make our mathematical lives a lot easier? In the case of \( \frac{\sqrt{6}}{\sqrt{2n}} \), you can combine the square roots into one by rewriting it as \( \sqrt{\frac{6}{2n}} \). This provides a cleaner look and makes it clear that you have simplified it down to \( \sqrt{\frac{3}{n}} \) since \( \frac{6}{2} = 3 \). Now, practical applications of this can be found in areas like physics, where simplifying expressions helps in calculations involving rates or measurements. For example, if you're calculating the speed of an object where \( n \) represents time and you want the speed in terms of a single expression, using simplified forms like \( \sqrt{\frac{3}{n}} \) can help deduce the relationship between motion parameters with greater clarity!