Simplified Form Of 5√8 - √18 - 2√2 A Step-by-Step Guide

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In the realm of mathematics, simplifying expressions involving radicals is a fundamental skill. Radicals, often represented by the square root symbol (√), can sometimes appear daunting, but with the right techniques, they can be tamed and expressed in their most concise form. This article delves into the simplification of the expression 5√8 - √18 - 2√2, providing a step-by-step guide that not only unravels the solution but also illuminates the underlying principles of radical simplification.

Understanding Radicals: The Building Blocks

To embark on our simplification journey, let's first solidify our understanding of radicals. A radical, in its simplest form, represents a root of a number. The square root of a number, denoted by √x, is a value that, when multiplied by itself, equals x. For instance, √9 = 3 because 3 * 3 = 9. However, not all numbers have perfect square roots. Numbers like 8 and 18, encountered in our expression, do not have whole number square roots, necessitating further simplification.

Simplifying radicals hinges on identifying perfect square factors within the radicand (the number under the radical symbol). A perfect square is a number that can be obtained by squaring an integer (e.g., 4, 9, 16, 25). By extracting these perfect square factors, we can reduce the radical to its simplest form. For example, √8 can be expressed as √(4 * 2), where 4 is a perfect square. This allows us to rewrite √8 as 2√2, as √4 equals 2.

Deconstructing the Expression: A Step-by-Step Approach

Now, let's apply these principles to our expression, 5√8 - √18 - 2√2. The key to simplifying this expression lies in breaking down the radicals √8 and √18 into their simplest forms.

Step 1: Simplifying √8

As we discussed earlier, √8 can be expressed as √(4 * 2). Recognizing 4 as a perfect square, we can rewrite this as:

√8 = √(4 * 2) = √4 * √2 = 2√2

Step 2: Simplifying √18

Similarly, we can simplify √18 by identifying its perfect square factors. 18 can be expressed as 9 * 2, where 9 is a perfect square. Thus,

√18 = √(9 * 2) = √9 * √2 = 3√2

Step 3: Substituting the Simplified Radicals

Now that we've simplified √8 and √18, we can substitute these values back into our original expression:

5√8 - √18 - 2√2 = 5(2√2) - 3√2 - 2√2

Step 4: Combining Like Terms

The expression now consists of terms involving the same radical, √2. We can combine these terms by treating √2 as a common factor:

5(2√2) - 3√2 - 2√2 = 10√2 - 3√2 - 2√2

Combining the coefficients, we get:

10√2 - 3√2 - 2√2 = (10 - 3 - 2)√2 = 5√2

Therefore, the simplified form of the expression 5√8 - √18 - 2√2 is 5√2.

The Power of Simplification: Why It Matters

Simplifying radical expressions is not merely an academic exercise; it holds practical significance in various mathematical contexts. Simplified expressions are easier to work with, making further calculations and manipulations more manageable. In fields like algebra, calculus, and physics, simplifying radicals can lead to more elegant and insightful solutions.

Moreover, simplified expressions provide a clearer representation of the underlying mathematical relationships. They allow us to readily compare and contrast different expressions, identify patterns, and gain a deeper understanding of the mathematical concepts involved.

Beyond the Basics: Advanced Simplification Techniques

While we've focused on simplifying square roots in this article, the principles extend to other types of radicals, such as cube roots and higher-order roots. The core idea remains the same: identify perfect nth power factors within the radicand and extract them to simplify the expression.

For instance, to simplify the cube root of 24 (∛24), we look for perfect cube factors. 24 can be expressed as 8 * 3, where 8 is a perfect cube (2^3). Thus,

∛24 = ∛(8 * 3) = ∛8 * ∛3 = 2∛3

Additionally, simplifying expressions involving radicals often requires rationalizing the denominator. This involves eliminating radicals from the denominator of a fraction, typically by multiplying both the numerator and denominator by a suitable expression.

Conclusion: Mastering the Art of Radical Simplification

Simplifying radical expressions is an essential skill in mathematics, empowering us to express complex expressions in their most concise and manageable forms. By understanding the principles of identifying perfect square factors and combining like terms, we can confidently tackle a wide range of radical simplification problems. The journey of simplifying 5√8 - √18 - 2√2 exemplifies this process, showcasing the power of breaking down complex problems into smaller, manageable steps. As you delve deeper into mathematics, the ability to simplify radicals will undoubtedly prove to be a valuable asset, unlocking new avenues of understanding and problem-solving.

In summary, the simplified form of the expression 5√8 - √18 - 2√2 is 5√2. This simplification was achieved by identifying perfect square factors within the radicals, extracting them, and then combining like terms. Mastering these techniques is crucial for success in various mathematical disciplines.