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Why √−1 Is Not on the Real Number Line

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The World of Numbers · Closing perspective · 2:59

You'll learn: Explain why squaring any real number cannot produce −1 and introduce the chapter’s final question.

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Why √−1 Is Not on the Real Number Line

2:59

Playing

Why √−1 Is Not on the Real Number Line

You'll learn: Explain why squaring any real number cannot produce −1 and introduce the chapter’s final question.

Now playing

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Chapter challenge problems

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Find More Reciprocals with Cyclic Repeating Blocks
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Find More Reciprocals with Cyclic Repeating Blocks
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What Does the Fourth Decimal Place Tell Us?
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What Does the Fourth Decimal Place Tell Us?
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Make Enough Space Between Fraction Numerators
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Prove That the Average Really Lies Between Two Numbers
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Understanding and proving identities

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Three Consecutive Squares Always Give Two
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Three Consecutive Squares Always Give Two
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An Identity Is an Equation True for Every Allowed Value
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An Identity Is an Equation True for Every Allowed Value
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Why the Square Identity Also Works for Negative Numbers
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Why the Square Identity Also Works for Negative Numbers
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When Is the Square of a Sum Bigger Than the Sum of Squares?
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Square a Binomial with Coefficients and Fractions
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Perfect-square factorisation

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Read a Perfect Square Backwards
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Read a Perfect Square Backwards
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Take Out a Common Factor Before Looking for a Square
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Derive the Square of a Difference by Substitution
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