Is Sqrt(32) + Sqrt(2) Rational Or Irrational? A Detailed Explanation

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Which of the following statements accurately describes the expression $\sqrt{32} + \sqrt{2}$?

Let's embark on a journey into the realm of numbers, where we'll dissect the expression 32+2\sqrt{32} + \sqrt{2} and determine its true nature. Our mission is to ascertain whether this expression represents a rational or irrational number, and to pinpoint its exact value. This exploration will not only enhance our understanding of number systems but also hone our problem-solving prowess in mathematics.

Deconstructing the Expression: Simplifying Radicals

At the heart of our investigation lies the expression 32+2\sqrt{32} + \sqrt{2}. To truly grasp its essence, we must first simplify the radical terms. Recall that a radical, denoted by the symbol \sqrt{}, signifies the root of a number. In this case, we're dealing with square roots, which ask: what number, when multiplied by itself, yields the number under the radical?

The key to simplifying radicals lies in identifying perfect square factors within the radicand (the number under the radical). For 32\sqrt{32}, we can break it down as follows:

32=16×2\sqrt{32} = \sqrt{16 \times 2}

Here, 16 is a perfect square (4 x 4 = 16). We can then use the property a×b=a×b\sqrt{a \times b} = \sqrt{a} \times \sqrt{b} to further simplify:

16×2=16×2=42\sqrt{16 \times 2} = \sqrt{16} \times \sqrt{2} = 4\sqrt{2}

Now, our expression transforms into:

42+24\sqrt{2} + \sqrt{2}

Combining Like Terms: A Symphony of Radicals

With the radicals simplified, we can now combine the terms. Notice that both terms contain the same radical, 2\sqrt{2}. This allows us to treat 2\sqrt{2} as a common factor and combine the coefficients:

42+2=(4+1)2=524\sqrt{2} + \sqrt{2} = (4 + 1)\sqrt{2} = 5\sqrt{2}

Thus, the simplified form of our expression is 525\sqrt{2}. This elegant simplification unveils the true nature of the expression, paving the way for our next crucial step.

Rational vs. Irrational: Deciphering the Number's Identity

Now comes the pivotal question: is 525\sqrt{2} rational or irrational? To answer this, we must delve into the definitions of these number categories.

A rational number can be expressed as a fraction p/q, where p and q are integers (whole numbers) and q is not zero. Rational numbers have decimal representations that either terminate (e.g., 0.5) or repeat in a pattern (e.g., 0.333...).

An irrational number, on the other hand, cannot be expressed as a fraction of integers. Their decimal representations are non-terminating and non-repeating. A classic example is π\pi (pi), which goes on infinitely without a repeating pattern.

Now, let's consider 2\sqrt{2}. It's a well-known fact that 2\sqrt{2} is irrational. Its decimal representation stretches on infinitely without any discernible pattern. When we multiply an irrational number by a rational number (in this case, 5), the result remains irrational.

Therefore, 525\sqrt{2} is an irrational number. This crucial finding narrows down our options and brings us closer to the final answer.

The Value Unveiled: 525\sqrt{2} in Numerical Terms

Having established the irrationality of our expression, let's pinpoint its approximate value. We know that 2\sqrt{2} is approximately 1.414. Multiplying this by 5, we get:

5×1.4147.075 \times 1.414 \approx 7.07

However, it's crucial to remember that this is an approximation. The true value of 525\sqrt{2} is an irrational number, meaning its decimal representation continues infinitely without repeating.

The Verdict: Choosing the Correct Statement

With our analysis complete, we can now confidently evaluate the given statements:

  • A. It is rational and equal to 4. Incorrect. We've established that the expression is irrational.
  • B. It is rational and equal to 5. Incorrect. Again, the expression is irrational.
  • C. It is irrational and equal to 525 \sqrt{2}. Correct. This statement aligns perfectly with our findings.
  • D. It is irrational and equal to 424\sqrt{2}. Incorrect. While the expression is irrational, its value is 525\sqrt{2}, not 424\sqrt{2}.

Therefore, the correct statement is C. 32+2\sqrt{32} + \sqrt{2} is irrational and equal to 525 \sqrt{2}.

Key Concepts: A Recap of Our Mathematical Journey

Before we conclude, let's recap the key concepts we've encountered in this mathematical exploration:

  • Radicals and Simplification: We learned how to simplify radicals by identifying perfect square factors within the radicand.
  • Combining Like Terms: We discovered how to combine terms with the same radical by treating the radical as a common factor.
  • Rational vs. Irrational Numbers: We differentiated between rational and irrational numbers based on their decimal representations and ability to be expressed as fractions.
  • Approximating Irrational Numbers: We explored how to approximate the value of irrational numbers using known approximations of their radical components.

Practical Applications: The Significance of Irrational Numbers

While irrational numbers may seem abstract, they play a crucial role in various fields, including:

  • Geometry: The ratio of a circle's circumference to its diameter, π\pi, is a famous irrational number. Irrational numbers also appear in geometric calculations involving square roots and other radicals.
  • Physics: Many physical constants, such as the speed of light, are irrational numbers.
  • Computer Science: Irrational numbers are used in algorithms for data compression and encryption.

Understanding irrational numbers is not just an academic exercise; it's a fundamental skill that empowers us to solve problems and make sense of the world around us.

Conclusion: Embracing the Beauty of Irrationality

In conclusion, our journey into the expression 32+2\sqrt{32} + \sqrt{2} has revealed its true identity as an irrational number equal to 525\sqrt{2}. This exploration has not only solidified our understanding of number systems but also highlighted the elegance and importance of irrational numbers in mathematics and beyond. By mastering these concepts, we equip ourselves with the tools to tackle complex problems and appreciate the intricate beauty of the mathematical universe. Remember, mathematics is not just about numbers and equations; it's about critical thinking, problem-solving, and a deeper understanding of the world we inhabit.

Which of the following statements accurately describes the expression 32+2\sqrt{32} + \sqrt{2}?

Is sqrt(32) + sqrt(2) Rational or Irrational? A Detailed Explanation