1 Choose 2
Combination Calculator
What is 1 choose 2?
Answer
1 choose 2 is
0
Order doesn't matter, no repeats: you can't choose 2 items from 1, so there are 0 ways.
2 > 1 → C(1, 2) = 0
If order matters (permutations): P(1, 2) = 0 too.
Row sum: 21 = 2 — all subsets of 1 item.
k = 2 is past the end of row 1.
See Also
- Random Number Generator - Pick a random whole number between two bounds
- Percent to Probability Converter - Convert Percents to "1 in X" Probability Chance
- Factors of a Number - List all Factors and Factor Pairs of a Number
n choose 2 for other n
FAQ
What is 1 choose 2?
1 choose 2 is 0
Why is 1 choose 2 zero?
You can't pick 2 different items when there are only 1, so there are no ways at all and the answer is 0, not an error. Often the numbers are swapped: 2 choose 1 = 2.
How many ways are there if order matters?
Still none: 2 different items can't be taken from 1 in any order, so P(1, 2) = 0 too.
See Also
- 1 Choose 0: Combinations C(1, 0)
- 1 Choose 1: Combinations C(1, 1)
- 1 Choose 3: Combinations C(1, 3)
- 1 Choose 4: Combinations C(1, 4)
- 2 Choose 0: Combinations C(2, 0)
- 2 Choose 1: Combinations C(2, 1)
- 2 Choose 2: Combinations C(2, 2)
- 2 Choose 3: Combinations C(2, 3)
- 2 Choose 4: Combinations C(2, 4)
- 2 Choose 5: Combinations C(2, 5)
- 2 Choose 10: Combinations C(2, 10)
- 3 Choose 0: Combinations C(3, 0)
- Число сочетаний из 1 по 2
- Combinaciones de 1 tomado de 2 en 2: C(1, 2)
- Combinação de 1 tomado 2 a 2: C(1, 2)