dec 21(part 1)(41:20)

Homework Review

  • Start with reviewing homework completion
  • Discuss discrepancies in notation and errors in solutions to questions
  • Example Corrections:
    • 92 corrected to 9/2
    • 10² corrected to 100 (instead of 102)

Question Breakdown

  • Discuss solvable questions individually or in total.

Question 1

  • Problem: Odd page count between 253 and 523
  • Approach:
    • Subtract page numbers to find total: 523 - 253 = 270
    • To find odd pages, calculate (n-1):
      • (523-253) - 1 * => yields total pages
    • Understand odd/even distribution based on the pages
Example Calculation
  • Between 1 and 5, total pages = 5 - 1 = 3
  • Odd numbers: 1, 3, 5 -> Total odd = 2
  • For 269: totals are counted as odd and even based on page numbering.

Question 2

  • Prime Factorization of 312:
    • Divisible by 2: 312 → 156 → 78 → 39 (not divisible by 2)
    • Next prime 3: 39/3 = 13 (prime)
    • Result: 2³ × 3¹ × 13¹ = 312.

Question 3

  • Calculate GCD and LCM for 42, 72, 84:
    • Use factorization or shared divisors for numbers
    • GCD noted as 6, LCM calculated.

Question 4

  • Identify perfect squares
    • Illustrate through examples such as:
      • 3/4 as perfect square (3/2)*(3/2)
    • Various products confirming perfect square status

Additional Perfect Square Considerations

  • Memorization of numbers is crucial, knowing squares/cubes can expedite calculations.

Questions on Powers

  • Reciprocal Definitions and Operations:
    • Definition:
      • Reciprocal of 3 is 1/3; key in calculations.
    • Simplifying powers using reciprocals.

Applying Orders of Magnitude

  • Understanding scientific notation through approximations.
  • Example: Estimate seconds in a year using:
    • Days x Hours x Minutes x Seconds -> Approximate values for manageable calculations.

Order of Operations (PEMDAS)

  • Reminder of operational hierarchy for calculations:
    • Parentheses, Exponents, Multiplication/Division, Addition/Subtraction

Powers and Exponents

  • Key properties include:
    • Same base multiplication: Add exponents
    • Division: Subtract exponents
    • Zero rule: Any number to the zero equals one.

Advanced Topics on Exponents

  • Discuss fractional exponents and their interpretation (e.g., how to handle roots and powers during calculations).
  • Clarification on roots - odd/even root handling.

Final Considerations during review session:

  • Memorization Importance:
    • Perfect squares, cubes, and their fundamental properties is essential for efficiency in problems.
  • Address any lingering questions or topics needing further clarity before transition to next lessons on real numbers and polynomials