The ISEE will directly and indirectly test your knowledge of number types. For example, a word problem may include rules where its values may only be integers or whole numbers.
Real Numbers (Numbers that Exists)
Natural Numbers
- include positive numbers
- do not include zero
- do not include negative numbers
- do not include decimals or fractions
Examples
✓ 1, 2, 3, 4
✘ -2, 0, 2.5
Whole Numbers
- includes positive numbers
- includes zero
- does not include negative numbers
- does not include decimals or fractions
Examples
✓ 0, 1, 2, 3, 4
✘ -4, -1.5, 3.7
Integers
- includes positive numbers
- includes zero
- includes negative numbers
- does not include decimals or fractions
Examples
✓ -2, -1, 0, 1, 2
✘ -4.3, -2.9, ½
Rational Numbers
- any number that can be represented as a fraction
Examples
✓ -3, 4.25, 0.004
✘ √2, √3, π
Irrational Numbers
- any number that cannot be represented as a fraction
Examples
✓ √2, √3, π
✘ 3.14, 22/7
Imaginary Numbers (Numbers That Don’t Exist)
Imaginary Numbers
- the square root (or even root) of a negative number
- squaring a negative number results in a positive number, thus the square root of a negative number does not exist
- generally represented as i = √-1
Examples
✓ √-2, 4√-25
✘ √7, √19
Complex Numbers
- includes a real part (a) and an imaginary part (bi)
- acts like a binomial in calculations
- a + bi
Examples
✓ 4 + 3i
✘ x3 – 3x = 14
