Flashcards › Math › Math
Types of Numbers
Natural, whole, integer, rational, irrational, real and special number families.
0 of 49 known
49 cards
- Natural (counting) numbersTerm1, 2, 3, 4, ...
- Whole numbersTerm0, 1, 2, 3, ...
- IntegersTerm..., −3, −2, −1, 0, 1, 2, 3, ...
- Rational numbersTermNumbers that can be written as a fraction of two integers
- Irrational numbersTermNumbers that cannot be written as a fraction
- Real numbersTermAll rational and irrational numbers
- Imaginary numbersTermMultiples of i, where i² = −1
- Complex numbersTermNumbers of the form a + bi
- Even numbersTermWhole numbers divisible by 2
- Odd numbersTermWhole numbers not divisible by 2
- Prime numbersTermNumbers above 1 with exactly two factors
- Composite numbersTermNumbers above 1 that are not prime
- Square numbersTerm1, 4, 9, 16, 25, ...
- Cube numbersTerm1, 8, 27, 64, 125, ...
- Triangular numbersTerm1, 3, 6, 10, 15, 21, ...
- Fibonacci numbersTerm1, 1, 2, 3, 5, 8, 13, 21, ...
- Perfect numbersTermNumbers equal to the sum of their proper factors: 6, 28, 496
- Is 6 perfect?TermYes: 1 + 2 + 3 = 6
- Is 28 perfect?TermYes: 1 + 2 + 4 + 7 + 14 = 28
- Palindromic numberTermA number that reads the same backward and forward121
- Twin primesTermPrimes that differ by 211 and 13
- Mersenne primeTermA prime of the form 2ⁿ − 17, 31, 127
- Pi is rational or irrational?TermIrrational
- √2 is rational or irrational?TermIrrational
- √9 is rational or irrational?TermRational (it equals 3)
- 0.5 is rational or irrational?TermRational
- 0.333... is rational or irrational?TermRational (1/3)
- Is e rational or irrational?TermIrrational
- Is zero positive or negative?TermNeither
- Is zero even?TermYes
- Is 1 prime?TermNo
- Is 0 an integer?TermYes
- Is −4 a whole number?TermNo
- Is −4 an integer?TermYes
- Is 3/4 an integer?TermNo, it is rational
- Is every integer a rational number?TermYes (n = n/1)
- Is every rational number an integer?TermNo
- Is every real number rational?TermNo
- Ordinal numbersTermFirst, second, third: tell position
- Cardinal numbersTermOne, two, three: tell how many
- Nominal numbersTermNumbers used as names or labels, like a jersey number
- Opposite of 7Term−7
- Reciprocal of 7Term1/7
- Absolute value of −7Term7
- Negative of a negativeTermA positive: −(−7) = 7
- GoogolTerm10^100
- GoogolplexTerm10 to the power of a googol
- InfinityTermNot a number; the idea of going on without end
- Golden ratioTermAbout 1.618, an irrational number: (1 + √5)/2
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