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Understanding Exponents and Operations

May 8, 2025

Lecture Notes: Exponents and Order of Operations

Introduction to Exponents

  • Concept of Repeated Operations
    • Addition: Repeating addition results in multiplication.
    • Multiplication: Repeating multiplication introduces the concept of exponents.
  • Defining Exponents
    • Base: The number being multiplied repeatedly.
    • Exponent: The number of times the base is multiplied by itself.
    • Example: (5^7) means 5 is multiplied by itself 7 times.

Terminology

  • Square: (5^2) is expressed as "5 squared."
  • Cube: (5^3) is referred to as "5 cubed."
  • General form: "5 to the power of n" where n is any number.

Evaluating Exponents

  • Example: (7^3 = 343) not 21.
  • First Power: Any number to the first power is itself (e.g., (11^1 = 11)).

Introduction to Order of Operations

  • Purpose: Ensures consistent mathematical results.
  • Mnemonic: PEMDAS (Parentheses, Exponents, Multiplication and Division (left to right), Addition and Subtraction (left to right)).

Detailed Explanation of Order of Operations

  • Step 1: Parentheses
    • Perform all operations inside parentheses first.
    • Different types of brackets are all considered parentheses.
  • Step 2: Exponents
    • Evaluate any terms with exponents next.
  • Step 3: Multiplication and Division
    • Perform from left to right as they appear.
  • Step 4: Addition and Subtraction
    • Also performed from left to right.

Applying Order of Operations

  • Examples
    • (8 + 3 \times 5): Calculate multiplication first.
    • (48 \div 3 \times 4): Perform division before multiplication.

Advanced Problems and Fractional Calculations

  • Parentheses and Nested Operations
    • Solve innermost parentheses first followed by outer brackets.
    • Example: (4 + (9 - 5)^2 - 7 \times 3)
  • Fractions as Division
    • Treat large fractions as implied parentheses.
    • Solve numerator and denominator separately before dividing.
    • Example: (\frac{25 + 8 \times 2 - 3^3}{5 \times (2 - 1)})

Area of a Square

  • Definition: All sides are equal in a square.
  • Calculating Area: Side squared (e.g., if side = 8, area = (8^2 = 64) square inches).
  • Perimeter: Sum of all sides (e.g., if side = 8, perimeter = 4 \times 8 = 32 inches).

Final Notes

  • Understanding Exponents and Order of Operations is crucial for solving complex expressions.
  • Homework: Practice problems on order of operations and areas as given.
  • Resources: Utilize online resources and math labs for additional help.

This concludes the notes on exponents and order of operations. Make sure to practice and reach out for help if needed.