Dab tsi yog universal teeb tsa hauv kev lag luam?
Dab tsi yog universal teeb tsa hauv kev lag luam?

Video: Dab tsi yog universal teeb tsa hauv kev lag luam?

Video: Dab tsi yog universal teeb tsa hauv kev lag luam?
Video: Tshuaj theem vim li cas thiaj tau nqi ?/ Siv kho mob dab tsi?/paris polyphylla use for? 2024, Kaum ib hlis
Anonim

UNIVERSAL SET . suav nrog tag nrho cov kev xaiv ua tau rau ib pawg khoom. RETRIEVAL SET . suav nrog cov khoom lag luam lossis cov khw muag khoom uas cov neeg siv khoom tuaj yeem nqa tau los ntawm MEMORT.

Ua li no, koj txhais li cas los ntawm universal teeb?

A universal teeb yog kev sau tag nrho cov khoom nyob rau hauv ib lub ntsiab lus tshwj xeeb lossis kev xav. Tag nrho lwm yam teeb nyob rau hauv lub moj khaum tsim subsets ntawm cov universal teeb , uas txhais tau tias yog ib tsab ntawv loj U . Cov khoom lawv tus kheej yog hu ua cov ntsiab lus lossis cov tswv cuab ntawm U.

Tom qab, lo lus nug yog, dab tsi yog lub ntsiab ntawm lub universal teeb? Cov txheej txheem universal yog txheej ntawm tag nrho cov ntsiab lus hauv qab kev xav , denoted los ntawm peev U los yog tej zaum peev E. Piv txwv li: Muab hais tias U = {5, 6, 7, 8, 9, 10, 11, 12}, teev cov ntsiab lus ntawm cov nram qab no teev.

Nyob rau hauv no txoj kev, dab tsi yog universal teeb thiab piv txwv?

Lus txhais: A Universal Teeb yog cov teeb ntawm tag nrho cov ntsiab nyob rau hauv kev txiav txim siab, denoted los ntawm peev.. Tag nrho lwm yam teeb yog subsets ntawm cov universal teeb . Piv txwv 2: ua. = {1, 2, 3, 4, 5, 6, 7, 8, 9}, A = {1, 2, 5, 6} thiab B = {3, 9}, kos ib daim duab Venn los sawv cev rau cov no teeb.

Qhov sib npaug ntawm Kev Ua lej yog dab tsi?

Sib npaug muaj cov ntsiab lus tib yam hauv lawv, txawm tias lawv tuaj yeem tawm ntawm kev txiav txim. Sib npaug teeb muaj cov ntsiab lus sib txawv tab sis muaj tib lub ntsiab lus. A set ua cardinality yog tus naj npawb ntawm cov ntsiab lus hauv teeb . Yog li ntawd, yog tias ob teeb muaj tib cardinality, lawv sib npaug!

Pom zoo: