Learn on PengienVision, Mathematics, Grade 8Chapter 1: Real Numbers

Lesson 7: More Properties of Exponents

In this Grade 8 lesson from enVision Mathematics Chapter 1, students learn the Zero Exponent Property (a⁰ = 1) and the Negative Exponent Property (a⁻ⁿ = 1/aⁿ) and practice rewriting expressions with zero or negative exponents using positive exponents. Students explore how these properties connect to the Quotient of Powers Property and apply them to simplify and evaluate exponential expressions.

Section 1

Zero as an Exponent

Property

a0=1a^0 = 1, if a0a \neq 0

This definition is based on the second law of exponents. For any non-zero number aa, the quotient anan\frac{a^n}{a^n} is equal to 1. Using the law of exponents, we can also write anan=ann=a0\frac{a^n}{a^n} = a^{n-n} = a^0. Therefore, it is logical to define a0a^0 as 1.

Examples

  • For a positive integer, 80=18^0 = 1.
  • For a negative integer, (55)0=1(-55)^0 = 1.
  • For an algebraic term where variables are non-zero, (2ab2)0=1(2ab^2)^0 = 1.

Section 2

Deriving Negative Exponents from Patterns

Property

As the exponent of a base decreases by 1, the value of the power is divided by the base. This pattern can be extended from positive exponents to zero and negative exponents to understand their meaning.

Examples

Book overview

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Chapter 1: Real Numbers

  1. Lesson 1

    Lesson 1: Rational Numbers as Decimals

  2. Lesson 2

    Lesson 2: Understand Irrational Numbers

  3. Lesson 3

    Lesson 3: Compare and Order Real Numbers

  4. Lesson 4

    Lesson 4: Evaluate Square Roots and Cube Roots

  5. Lesson 5

    Lesson 5: Solve Equations Using Square Roots and Cube Roots

  6. Lesson 6

    Lesson 6: Use Properties of Integer Exponents

  7. Lesson 7Current

    Lesson 7: More Properties of Exponents

  8. Lesson 8

    Lesson 8: Use Powers of 10 to Estimate Quantities

  9. Lesson 9

    Lesson 9: Understand Scientific Notation

  10. Lesson 10

    Lesson 10: Operations with Numbers in Scientific Notation

Lesson overview

Expand to review the lesson summary and core properties.

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Section 1

Zero as an Exponent

Property

a0=1a^0 = 1, if a0a \neq 0

This definition is based on the second law of exponents. For any non-zero number aa, the quotient anan\frac{a^n}{a^n} is equal to 1. Using the law of exponents, we can also write anan=ann=a0\frac{a^n}{a^n} = a^{n-n} = a^0. Therefore, it is logical to define a0a^0 as 1.

Examples

  • For a positive integer, 80=18^0 = 1.
  • For a negative integer, (55)0=1(-55)^0 = 1.
  • For an algebraic term where variables are non-zero, (2ab2)0=1(2ab^2)^0 = 1.

Section 2

Deriving Negative Exponents from Patterns

Property

As the exponent of a base decreases by 1, the value of the power is divided by the base. This pattern can be extended from positive exponents to zero and negative exponents to understand their meaning.

Examples

Book overview

Jump across lessons in the current chapter without opening the full course modal.

Continue this chapter

Chapter 1: Real Numbers

  1. Lesson 1

    Lesson 1: Rational Numbers as Decimals

  2. Lesson 2

    Lesson 2: Understand Irrational Numbers

  3. Lesson 3

    Lesson 3: Compare and Order Real Numbers

  4. Lesson 4

    Lesson 4: Evaluate Square Roots and Cube Roots

  5. Lesson 5

    Lesson 5: Solve Equations Using Square Roots and Cube Roots

  6. Lesson 6

    Lesson 6: Use Properties of Integer Exponents

  7. Lesson 7Current

    Lesson 7: More Properties of Exponents

  8. Lesson 8

    Lesson 8: Use Powers of 10 to Estimate Quantities

  9. Lesson 9

    Lesson 9: Understand Scientific Notation

  10. Lesson 10

    Lesson 10: Operations with Numbers in Scientific Notation