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.