Know that numbers that are not rational are called irrational

Start lessonBegins with Rational and irrational numbers · Slides

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8.NS.A.1

**8.NS.A.1**: Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion which repeats eventually into a rational number.

8.NS.A.1: Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion which repeats eventually into a rational number.

What you'll learn

Define rational and irrational numbers and classify given numbers correctly into one category or the other
Explain informally that every real number has a decimal expansion, and that a rational number's decimal expansion either terminates or eventually repeats
Show, using examples and informal reasoning, why long division of any fraction p/q must eventually produce a repeating decimal
Convert a repeating decimal to its equivalent fraction form using the algebraic subtraction technique
Recognize that irrational numbers -- such as sqrt2 and pi -- have decimal expansions that neither terminate nor repeat, and that they cannot be expressed as a ratio of two integers

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Rational and irrational numbers

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