Áireamhán Teaglaim (nCr)
Na bealaí a roghnaíonn r míreanna ó n a chomhaireamh nuair nach bhfuil ordú ábhartha.
Torthaí a nuashonrú mar a chlóscríobh tú.
Maidir leis an áireamhán seo
combination counts how many ways you can choose r items from a set of n when order does not matter — picking the same group in a different sequence counts once. This calculator returns the exact count, the formula, and the matching number of ordered arrangements (nPr) for comparison. For 10 items taken 3 at a time there are 120 distinct groups. Combinations are always smaller than permutations because each unordered group corresponds to r! different orderings, so nCr = nPr ÷ r!. As with permutations, r cannot exceed n.Combinations answer "how many groups?" — the odds in a lottery, the number of possible five-card poker hands, ways to pick a committee, or terms in a binomial expansion. The value nCrCombinationsCombinations answer "how many groups?" —The formulaCombinationsCombinations answer "how many groups?" — the odds in a lottery, the number of possible five-card poker hands, ways to pick a committee, or terms in a binomial expansion.The value nCrCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombinationsCombination
Ceisteanna Coitianta
Cad é an fhoirmle teaglaim?
nCr = n! / (r! × (n − r)!). I gcás 10 n-earra a thógtar 3 ag an am: 120 grúpaí éagsúla.
Cén fáth go bhfuil nCr níos lú ná nPr?
Déanann na comhcheangail neamhaird ar ord, mar sin fhreagraíonn gach grúpa neamhordaithe do r! permutations ordaithe. Sin é an fáth nCr = nPr ÷ r!.
Cén uair ba chóir dom meascán a úsáid?
Nuair nach bhfuil ordú ábhar: uimhreacha crannchuir, lámh cártaí, coiste a roghnú, nó aon rogha ina bhfuil an grúpa cad a áirítear, ní a shocrú.
Cad is comhéifeacht dénártha ann?
Is ainm eile é ar nCr, an luach "n roghnaigh r" a thaispeántar sa teoirim dénominiúil agus a chruthaíonn na hiontrálacha de thriantán Pascal.
Cad é nC0 nó nCn?
Tá an dá chomhionann le 1 — tá bealach amháin ann chun aon cheann a roghnú, agus bealach amháin chun gach ceann acu a roghnú.
An dtaispeánann an uirlis seo permutations freisin?
Taispeánann sé nPr = nCr × r! in éineacht leis an meascán ionas gur féidir leat comparáid a dhéanamh idir comhaireamh ordaithe agus neamhordaithe.
API — úsáid an áireamhán seo ó chód
Glaoigh ar an áireamhán seo mar chríochphointe JSON saor in aisce - níl aon eochair ag teastáil. Seol na luachanna réimse thíos mar pharaiméadair cheist nó JSON. Léigh an doiciméadú iomlán API →
Deireadhphointe
GET https://calculator.free/api/v1/combination/curl
curl "https://calculator.free/api/v1/combination/?n=10&r=3"JavaScript fetch()
const r = await fetch(
"https://calculator.free/api/v1/combination/?" + new URLSearchParams({
"n": "10",
"r": "3"
}));
const data = await r.json();
console.log(data.results);Is meastacháin iad na torthaí le haghaidh treoir ghinearálta amháin, ní comhairle airgeadais, leighis nó cánach.