Understanding Roots Between Consecutive Integers

Sep 9, 2024

Key Concepts from the Lecture

Example 1: Finding Consecutive Integers for the Square Root of 7

  • Objective: Determine between which two consecutive integers the square root of 7 lies.
  • Consecutive Integers: Two whole numbers that surround a given value.
  • Approach:
    • Recognize that the square root of a number will be between the square roots of two perfect squares.
    • Recall some perfect squares:
      • (2^2 = 4)
      • (3^2 = 9)
    • Since 7 is between 4 and 9, the square root of 7 is between the square roots of these values.
    • Conclusion:
      • (\sqrt{4} = 2)
      • (\sqrt{9} = 3)
    • Therefore, the square root of 7 is between 2 and 3.

Example 2: Finding Consecutive Integers for the Cube Root of 100

  • Objective: Determine between which two consecutive integers the cube root of 100 lies.
  • Approach:
    • Recognize that the cube root of a number will be between the cube roots of two perfect cubes.
    • Recall some perfect cubes:
      • (2^3 = 8)
      • (3^3 = 27)
      • (4^3 = 64)
      • (5^3 = 125)
    • Since 100 is between 64 and 125, the cube root of 100 is between the cube roots of these values.
    • Conclusion:
      • (\sqrt[3]{64} = 4)
      • (\sqrt[3]{125} = 5)
    • Therefore, the cube root of 100 is between 4 and 5.

Summary

  • To find between which two integers a root lies, identify the perfect squares (or cubes) surrounding the given number.
  • Utilize knowledge of basic perfect squares and cubes to deduce the integers between which the root of a number lies.