
April 21, 2023

Nagendra Prasad Krishnam

 Natural numbers: All positive integers (excluding zero) are natural numbers. Examples: 1, 2, 3, 4, 5, etc.
 Complex numbers: Any number that can be expressed in the form a + bi, where a and b are real numbers and i is the imaginary unit (where i^2 = 1), is a complex number. Examples: 2 + 3i, 4 + 2i, 5i, etc.
 Imaginary numbers: Any complex number where the real part is 0 is an imaginary number. Examples: 3i, 2i, etc.
 Composite numbers: Any number that has more than two factors is a composite number. In other words, it can be divided by more than just 1 and itself. Examples: 4 (factors are 1, 2, and 4), 6 (factors are 1, 2, 3, and 6), 8 (factors are 1, 2, 4, and 8), etc.
 Complex conjugates: If a complex number is a + bi, then its complex conjugate is a – bi. The complex conjugate has the same real part but the imaginary part is the negative of the original. Example: The complex conjugate of 3 + 4i is 3 – 4i.
 Even numbers: Any number that is divisible by 2 is an even number. Examples: 2, 4, 6, 8, 10, etc.
 Odd numbers: Any number that is not divisible by 2 is an odd number. Examples: 1, 3, 5, 7, 9, etc.
 Prime numbers: Any number that is only divisible by 1 and itself is a prime number. Examples: 2, 3, 5, 7, 11, 13, etc.
 Integers: All whole numbers (positive, negative, or zero) are integers. Examples: 3, 2, 1, 0, 1, 2, 3, etc.
 Whole numbers: All positive integers (including zero) are whole numbers. Examples: 0, 1, 2, 3, etc.
 Decimal numbers: Any number that includes a decimal point is a decimal number. Examples: 0.5, 3.14159, 2.75, etc.
 Fractional numbers: Any number that can be expressed as a ratio of two integers (such as a/b) is a fractional number. Examples: 1/2, 2/3, 3/4, etc.
 Rational numbers: Any number that can be expressed as a ratio of two integers (such as a/b) is a rational number. Examples: 1/2, 2/3, 3/4, etc. All integers and fractions are rational numbers.
 Irrational numbers: Any number that cannot be expressed as a ratio of two integers is an irrational number. Examples: pi (3.14159…), the square root of 2 (√2), etc. These numbers have decimal expansions that go on forever without repeating.