best answer > Is a rational or irrational number?- QuesHub | Better Than Quora
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  • Oliver Davis——Works at the International Finance Corporation, Lives in Washington, D.C., USA.

    As a mathematical expert, I am well-versed in the concepts of rational and irrational numbers. Let's delve into the distinction between these two types of numbers.

    A rational number is any number that can be expressed as the quotient or fraction \( \frac{p}{q} \) where \( p \) and \( q \) are integers and \( q \neq 0 \). These are numbers that can be written as a ratio of two integers, and they can be either finite decimals or infinite repeating decimals. For instance, \( \frac{1}{2} \) is a rational number because it can be expressed as a fraction, and \( 0.5 \) is also rational because it is a finite decimal that can be expressed as \( \frac{1}{2} \). Similarly, \( 0.333... \) (where the 3 repeats indefinitely) is a rational number because it can be expressed as \( \frac{1}{3} \).

    On the other hand, an irrational number is a number that cannot be expressed as a simple fraction. This means it's a number that cannot be written as \( \frac{p}{q} \) where \( p \) and \( q \) are integers and \( q \neq 0 \). When an irrational number is written in decimal form, it has a non-repeating, non-terminating decimal expansion. This means that the digits after the decimal point continue indefinitely without any repeating pattern. Examples of irrational numbers include \( \pi \) (pi), which is approximately 3.14159, and \( \sqrt{2} \) (the square root of 2), which is approximately 1.41421. These numbers are irrational because they cannot be expressed as a fraction of two integers, and their decimal representations do not repeat.

    It's important to note that irrational numbers are not just non-repeating; they are also non-terminating. This means that the decimal representation of an irrational number goes on forever without end. In contrast, rational numbers, whether they are finite decimals or infinite repeating decimals, have a decimal representation that either ends after a certain number of digits or repeats a pattern indefinitely.

    The distinction between rational and irrational numbers is fundamental in mathematics, as it helps us understand the nature of real numbers and the properties of various mathematical operations. Rational numbers form a dense subset of the real numbers, meaning that between any two rational numbers, there is always another rational number. However, irrational numbers fill in the gaps, ensuring that the real number line is continuous and unbroken.

    In conclusion, the key to identifying whether a number is rational or irrational lies in its representation as a fraction and its decimal expansion. If a number can be expressed as a fraction of two integers and has a finite or repeating decimal expansion, it is rational. If it cannot be expressed as such and has a non-repeating, non-terminating decimal expansion, it is irrational.

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    +149932024-05-25 16:01:22
  • Amelia Kim——Studied at the University of Seoul, Lives in Seoul, South Korea.

    An irrational number is a number that is NOT rational. It cannot be expressed as a fraction with integer values in the numerator and denominator. Examples: When an irrational number is expressed in decimal form, it goes on forever without repeating.read more >>
    +119962023-06-09 01:46:16

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