🔟elementary algebra review

6.2 Use Multiplication Properties of Exponents

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Exponents are powerful tools in algebra, allowing us to simplify complex expressions. They represent repeated multiplication, making it easier to work with large numbers and variables. Understanding exponent properties is crucial for solving equations and manipulating algebraic expressions efficiently.

In this section, we'll explore key exponent properties like the product, power, and product-to-power rules. We'll also learn about zero and negative exponents, scientific notation, and how to combine these properties to tackle more complex problems.

Exponent Properties

Simplification with exponent properties

  • Exponents represent repeated multiplication of a base number ($2^3 = 2 \times 2 \times 2 = 8$)
  • Properties of exponents simplify expressions by combining or distributing exponents
    • Product property adds exponents of like bases ($a^m \times a^n = a^{m+n}$)
    • Power property multiplies exponents when a power is raised to another power ($(a^m)^n = a^{m \times n}$)
    • Product to power property distributes an exponent to each factor inside parentheses ($(a \times b)^n = a^n \times b^n$)

Product property of exponents

  • Multiply terms with the same base by adding their exponents ($x^3 \times x^4 = x^{3+4} = x^7$)
  • Bases must match for the product property to apply ($2^3 \times 3^3 \neq 6^3$)
  • Simplifies expressions by combining like bases and adding exponents

Power property of exponents

  • Raise a power to another power by multiplying the exponents ($(y^2)^3 = y^{2 \times 3} = y^6$)
  • Applies to expressions within parentheses raised to a power ($((2x)^2)^3 = (2x)^{2 \times 3} = (2x)^6 = 64x^6$)
  • Simplifies expressions by distributing exponents to powers

Product to power property

  • Raise an expression inside parentheses to a power by distributing the exponent to each term ($(2x)^3 = 2^3 \times x^3 = 8x^3$)
  • Multiplies out each factor within the parentheses by the outside exponent
  • Simplifies expressions by expanding parentheses and applying the power to each term

Laws of Exponents

  • Zero exponent: Any number (except 0) raised to the power of 0 equals 1 ($a^0 = 1$)
  • Negative exponents: Represent reciprocals of positive exponents ($a^{-n} = \frac{1}{a^n}$)
  • Scientific notation: Expresses very large or small numbers using powers of 10 ($3.5 \times 10^6$)

Combining exponent properties

  • Break down complex expressions into smaller parts
  • Identify and apply the appropriate exponent property for each part
  • Simplify each part using the applicable property
  • Combine the simplified parts to obtain the final answer
    1. Simplify $(3x^2y)^3$ using the product to power property: $3^3 \times (x^2)^3 \times y^3 = 27x^6y^3$
    2. Simplify $(2xy^2)^2$ using the product to power property: $2^2 \times x^2 \times (y^2)^2 = 4x^2y^4$
    3. Multiply the simplified parts using the product property: $27x^6y^3 \times 4x^2y^4 = 108x^8y^7$

Monomial multiplication using exponents

  • Monomials are expressions with a single term ($4x^3y^2$)
  • Multiply monomials by multiplying coefficients and adding exponents of like bases ($(4x^3y^2) \times (2xy^3) = 8x^4y^5$)
  • Simplify the result by combining like terms and applying exponent properties ($12x^2y \times 3xy^2 = 36x^3y^3$)