Course Content
CBSE Class 8 Maths
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๐Ÿ“Œ Classification of Numbers in Mathematics

Numbers are classified into different types based on their properties. Below is a structured breakdown:


๐Ÿ”ข 1. Natural Numbers (N) & Whole Numbers (W)

โœ” Natural Numbers (N): Counting numbers starting from 1.
๐Ÿ“Œ Examples: 1, 2, 3, 4, 5, โ€ฆ

โœ” Whole Numbers (W): Natural numbers + 0.
๐Ÿ“Œ Examples: 0, 1, 2, 3, 4, โ€ฆ

comparison table


๐Ÿ”ข 2. Integers (Z)

โœ” Integers (Z): Whole numbers and their negatives.
๐Ÿ“Œ Examples: โ€ฆ -3, -2, -1, 0, 1, 2, 3, โ€ฆ

๐Ÿ’ก Fact: Every whole number is an integer, but not every integer is a whole number.


๐Ÿ”ข 3. Rational Numbers (Q)

โœ” Rational Numbers (Q): Numbers that can be written as a fraction (p/q), where:

  • p and q are integers
  • q โ‰  0

๐Ÿ“Œ Examples:

  • 1/2
  • 3/4
  • 0.3333… = 1/3 (Repeating Decimal)
  • 0.25 = 1/4 (Terminating Decimal)

๐Ÿ”ข 4. Irrational Numbers

โœ” Irrational Numbers: Cannot be written as fractions and have non-terminating, non-repeating decimals.

๐Ÿ“Œ Examples:

  • ฯ€ = 3.1415926535… (never repeats)
  • โˆš2 = 1.41421356…

key difference


๐Ÿ”ข 5. Real Numbers (R)

โœ” Real Numbers (R): All Rational and Irrational Numbers combined.
โœ” Represented on a number line.
โœ” Includes: Integers, fractions, terminating & repeating decimals, surds.

๐Ÿ’ก Fun Fact: Every number you’ve ever used in daily life is a Real Number!


๐Ÿ”ข 6. Prime & Composite Numbers

โœ” Prime Numbers: Divisible only by 1 and itself.
๐Ÿ“Œ Examples: 2, 3, 5, 7, 11, 13, 17, 19…

โœ” Composite Numbers: Have more than two factors.
๐Ÿ“Œ Examples: 4 (1,2,4), 6 (1,2,3,6), 8 (1,2,4,8)


๐Ÿ”ข 7. Even & Odd Numbers

โœ” Even Numbers: Divisible by 2.
๐Ÿ“Œ Examples: 2, 4, 6, 8, 10โ€ฆ

โœ” Odd Numbers: Not divisible by 2.
๐Ÿ“Œ Examples: 1, 3, 5, 7, 9โ€ฆ


๐Ÿ”ข 8. Complex Numbers (C)

โœ” Complex Numbers: Extend real numbers by including imaginary numbers (i), where iยฒ = -1.

๐Ÿ“Œ General form: (a + bi), where a, b are real numbers.

๐Ÿ“Œ Examples:

  • 2 + 3i
  • -5 + 4i

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