Under what circumstance is it of interest to divide the radicals for simplifying a fraction involving square roots what principal permits the division of radicals in this manner

1 answer

Dividing radicals to simplify a fraction involving square roots is often of interest when you're working with expressions that may be easier to handle in a simplified form. The primary principle that permits the division of radicals in this manner is based on the properties of square roots.

Principal for Division of Radicals

The key property of radicals that allows division and simplification is:

\[ \sqrt{a} / \sqrt{b} = \sqrt{a / b} \]

Circumstances for Interest

  1. Simplifying Expressions: When dealing with complex expressions, simplifying them can make calculations and comparisons easier. For instance, in algebraic fractions, reducing the degree of the radical may help in further calculations or comparisons with other expressions.

  2. Rationalizing Denominators: Often, when you have a square root in the denominator, it's desirable to remove it by multiplying the numerator and the denominator by the radical. However, if the expression allows it, simplifying via division first can sometimes lead to a more manageable expression.

  3. Finding Exact Values: When evaluating or simplifying expressions, dividing square roots can help in obtaining more concise and exact forms, particularly in calculus, where derivatives or integrals might be needed.

  4. Comparing Rates or Proportions: When preparing rates or proportions involving square roots, simplifying the expression can provide clearer insights.

Example

If you have:

\[ \frac{\sqrt{9}}{\sqrt{16}} = \frac{3}{4} \]

You can also express it as:

\[ \sqrt{\frac{9}{16}} = \sqrt{\frac{9}{16}} = \frac{3}{4} \]

Both approaches yield the same final result.

Overall, anytime you have radicals involved, and you see a fraction, considering division of radicals can lead to simpler or more elegant forms. Just ensure that you're operating within the principal allowed by the properties of square roots.