Dab tsi yog qhov sib npaug hauv kev ua lej tsis sib xws?
Dab tsi yog qhov sib npaug hauv kev ua lej tsis sib xws?

Video: Dab tsi yog qhov sib npaug hauv kev ua lej tsis sib xws?

Video: Dab tsi yog qhov sib npaug hauv kev ua lej tsis sib xws?
Video: 8 yam tsis txhob ua thaum sib deev tag tsis li yuav phom sij txog lub neej txoj sia. 2024, Kaum ib hlis
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Hauv lej , ib sib npaug Kev sib raug zoo yog ib qho kev sib raug zoo binary uas yog reflexive, symmetric thiab transitive. Kev sib raug zoo "yog sib npaug" yog qhov piv txwv canonical ntawm ib qho sib npaug Relation, qhov twg rau tej yam khoom a, b, thiab c: a = a (reflexive property), yog a = b thiab b = c ces a = c (transitive property).

Tsis tas li ntawd, qhov sib npaug hauv lej yog dab tsi?

Sib npaug txhais tau hais tias sib npaug ntawm tus nqi, kev ua haujlwm, lossis lub ntsiab lus. Hauv lej , sib npaug cov lej yog cov lej uas sau txawv tab sis sawv cev tib tus lej.

Dab tsi yog txoj cai ntawm tus kheej hauv kev ua lej tsis sib xws? Yog li cov kev cai lij choj , p∧T≡p, txhais tau hais tias kev sib txuas ntawm ib kab lus p nrog qhov kev txiav txim siab tautology T yuav ib txwm muaj qhov tseeb tus nqi raws li p (piv txwv li, yuav yog qhov sib npaug nrog p). Nws txhais tau hais tias qhov kev tsis sib haum xeeb ntawm ib kab lus p nrog qhov kev txiav txim siab tautology T yuav ib txwm muaj tseeb (yuav nws tus kheej yog tautology).

Tsis tas li ntawd, piv txwv li kev sib npaug sib npaug yog dab tsi?

Ib kev sib npaug ntawm lub teeb S, yog a kev sib raug zoo ntawm S uas yog reflexive, symmetrical thiab transitive. Piv txwv : Cia S = ℤ thiab txhais R = {(x, y) | x thiab y muaj tib qhov sib npaug} piv txwv li, x thiab y yog ob qho tib si lossis ob qho tib si khib. Lub parity kev sib raug zoo yog ib kev sib npaug.

Txoj cai lij choj ntawm kev sib npaug yog dab tsi?

Hauv logic thiab lej, nqe lus thiab hais tias yog logic sib npaug , yog hais tias lawv muaj pov thawj los ntawm ib leeg nyob rau hauv ib pawg ntawm axioms, los yog muaj qhov tseeb tus nqi nyob rau hauv txhua tus qauv. Cov logical sib npaug ntawm thiab qee zaum qhia tias yog,, lossis., nyob ntawm qhov kev sau ntawv siv.

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