Ib nqe lus biconditional yog ib nqe lus sib txuas lus nrog nws cov lus sib tham. Yog li, ib qho xwm txheej muaj tseeb yog tias thiab tsuas yog tias lwm qhov yog qhov tseeb thiab. Nws feem ntau siv cov lus, "yog tias thiab tsuas yog" lossis luv luv "iff." Nws siv ob lub xub los ceeb toom koj tias qhov xwm txheej yuav tsum muaj tseeb hauv ob qho kev qhia.
Ib qho piv txwv ntawm ib nqe lus biconditional yog dab tsi?
Bicconditional Nqe Lus piv txwv
Lub polygon tsuas muaj plaub sab yog tias thiab tsuas yog lub polygon yog plaub fab. Lub polygon yog quadrilateral yog thiab tsuas yog tias lub polygon tsuas muaj plaub sab. Lub quadrilateral muaj plaub congruent sab thiab cov ces kaum yog thiab tsuas yog hais tias lub quadrilateral yog ib tug square.
Lub ntsiab lus ntawm kev sib tw yog dab tsi?
: kev sib raug zoo ntawm ob txoj lus uas muaj tseeb tsuas yog thaum ob qhov kev tawm tswv yim ib txhij muaj tseeb lossis tsis tseeb - saib Qhov Tseeb.
Yuav ua li cas yog ob lub ntsiab lus?
Rules in Biconditional Propositions
A biconditional proposition yog muaj tseeb yog tias ob qho khoom muaj qhov tseeb tib yam. Yog li, yog tias ib qho tseeb thiab qhov tsis tseeb, lossis yog ib qho tsis tseeb thiab lwm qhov tseeb, ces qhov kev xav ntawm biconditional yog cuav.
nqe lus twg yog qhov tseeb?
Yuav kom muaj tseeb, ob qho tib si nqe lus thiab nws cov lus sib tham yuav tsum muaj tseeb. Ib nqe lus tseeb biconditional yog muaj tseeb ob qho tib si "forward" thiabrov qab". Txhua lub ntsiab lus tuaj yeem sau tau raws li cov lus hais muaj tseeb.
