Learn on PengiPengi Math (Grade 8)Chapter 2: Exponents, Radicals, and Scientific Notation

Lesson 2: Exponent Properties: Products, Quotients, and Powers

In this Grade 8 lesson from Pengi Math Chapter 2, students learn to apply the Product Rule, Quotient Rule, Power of a Power rule, and Power of a Product rule to simplify exponential expressions. Learners practice combining multiple exponent properties step by step to rewrite and reduce expressions with the same base. This lesson builds essential fluency with exponents as part of a broader unit on exponents, radicals, and scientific notation.

Section 1

The Product Rule of Exponents

Property

For any real number aa and natural numbers mm and nn, the product rule of exponents states that

aman=am+na^m \cdot a^n = a^{m+n}

Examples

  • To simplify g4g2g^4 \cdot g^2, we add the exponents: g4+2=g6g^{4+2} = g^6.
  • To simplify (5)4(5)(-5)^4 \cdot (-5), we recognize that (5)(-5) is (5)1(-5)^1. So, we have (5)4+1=(5)5(-5)^{4+1} = (-5)^5.
  • We can combine multiple terms: y3y6y2=y3+6+2=y11y^3 \cdot y^6 \cdot y^2 = y^{3+6+2} = y^{11}.

Explanation

When multiplying terms with the same base, keep the base and add the exponents. This is a shortcut for counting all the individual factors. For example, x2x3x^2 \cdot x^3 means (xx)(xxx)(x \cdot x) \cdot (x \cdot x \cdot x), which is simply x5x^5.

Section 2

Multiplicative Inverse Property and Negative Exponents

Property

The multiplicative inverse (reciprocal) of ana^n is ana^{-n}, and vice versa: anan=a0=1a^n \cdot a^{-n} = a^0 = 1

anan=1 where a0a^n \cdot a^{-n} = 1 \text{ where } a \neq 0

Section 3

The Quotient Rule for Exponents

Property

To divide two powers with the same base, subtract the exponent of the denominator from the exponent of the numerator. For any non-zero number aa, and for whole numbers mm and nn where m>nm > n:

aman=amn\frac{a^m}{a^n} = a^{m-n}

Examples

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Chapter 2: Exponents, Radicals, and Scientific Notation

  1. Lesson 1

    Lesson 1: Integer Exponents and Properties

  2. Lesson 2Current

    Lesson 2: Exponent Properties: Products, Quotients, and Powers

  3. Lesson 3

    Lesson 3: Square Roots and Cube Roots

  4. Lesson 4

    Lesson 4: Applications and Approximations of Square Roots

  5. Lesson 5

    Lesson 5: Introduction to Scientific Notation

  6. Lesson 6

    Lesson 6: Operations with Scientific Notation

Lesson overview

Expand to review the lesson summary and core properties.

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Section 1

The Product Rule of Exponents

Property

For any real number aa and natural numbers mm and nn, the product rule of exponents states that

aman=am+na^m \cdot a^n = a^{m+n}

Examples

  • To simplify g4g2g^4 \cdot g^2, we add the exponents: g4+2=g6g^{4+2} = g^6.
  • To simplify (5)4(5)(-5)^4 \cdot (-5), we recognize that (5)(-5) is (5)1(-5)^1. So, we have (5)4+1=(5)5(-5)^{4+1} = (-5)^5.
  • We can combine multiple terms: y3y6y2=y3+6+2=y11y^3 \cdot y^6 \cdot y^2 = y^{3+6+2} = y^{11}.

Explanation

When multiplying terms with the same base, keep the base and add the exponents. This is a shortcut for counting all the individual factors. For example, x2x3x^2 \cdot x^3 means (xx)(xxx)(x \cdot x) \cdot (x \cdot x \cdot x), which is simply x5x^5.

Section 2

Multiplicative Inverse Property and Negative Exponents

Property

The multiplicative inverse (reciprocal) of ana^n is ana^{-n}, and vice versa: anan=a0=1a^n \cdot a^{-n} = a^0 = 1

anan=1 where a0a^n \cdot a^{-n} = 1 \text{ where } a \neq 0

Section 3

The Quotient Rule for Exponents

Property

To divide two powers with the same base, subtract the exponent of the denominator from the exponent of the numerator. For any non-zero number aa, and for whole numbers mm and nn where m>nm > n:

aman=amn\frac{a^m}{a^n} = a^{m-n}

Examples

Book overview

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

Continue this chapter

Chapter 2: Exponents, Radicals, and Scientific Notation

  1. Lesson 1

    Lesson 1: Integer Exponents and Properties

  2. Lesson 2Current

    Lesson 2: Exponent Properties: Products, Quotients, and Powers

  3. Lesson 3

    Lesson 3: Square Roots and Cube Roots

  4. Lesson 4

    Lesson 4: Applications and Approximations of Square Roots

  5. Lesson 5

    Lesson 5: Introduction to Scientific Notation

  6. Lesson 6

    Lesson 6: Operations with Scientific Notation