2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Claim: f yog txhaj yog thiab tsuas yog nws muaj sab laug sab laug . Pov thawj: Peb yuav tsum (⇒) ua pov thawj tias yog f yog txhaj tshuaj ces nws muaj sab laug inverse, thiab (⇐) tias yog f muaj sab laug inverse, ces nws yog txhaj. (⇒) Piv txwv tias f yog txhaj. Peb xav tsim ib txoj haujlwm g: B→A xws li g ∘ f=idA.
Puas surjective yog thiab tsuas yog txhaj tshuaj?
Tshwj xeeb, yog tias X thiab Y yog qhov kawg uas muaj tib lub ntsiab lus, ces f: X → Y yog surjective if thiab tsuas yog f yog txhaj. Muab ob teev X thiab Y, cov ntawv sau X ≤ Y yog siv los hais tias X yog khoob lossis tias muaj qhov cuam tshuam los ntawm Y mus rau X.
Koj paub li cas yog qhov ua haujlwm yog Txhaj?
A muaj nuj nqi f yog txhaj yog thiab tsuas yog thaum twg f(x)=f(y), x=y. yog ib qho kev txhaj tshuaj.
Yuav ua li cas tsis txhaj tshuaj?
Lub luag haujlwm tsis tas yuav txhaj tshuaj lossis qhov kev txiav txim siab kom pom cov duab thim rov qab ntawm lub teeb. Piv txwv li, qhov muaj nuj nqi f(n)=1 nrog domain thiab codomain tag nrho cov zauv ntuj Page 8 2. PROPERTIES OF FUNCTIONS 118 yuav muaj cov duab inverse nram qab no: f−1({1})=N thiab f−1({5, 6, 7, 8, 9})=∅.
Yuav ua li cas txhaj tshuaj?
Hauv kev ua lej, ib qho kev txhaj tshuaj (tseem hu ua kev txhaj tshuaj, lossis ib-rau-ib txoj haujlwm) yog ua haujlwm f uas qhia cov ntsiab lus sib txawv rau cov ntsiab lus sib txawv ; uas yog, f(x1)=f(x2) implies x1=x2. Hauv lwm lo lus, txhua lub ntsiab lus ntawm lub luag haujlwm lub codomain yog cov duab ntawm feem ntau ntawm nws lub npe.
Pom zoo:
Cov tshuaj tiv thaiv dab tsi rau kev txhaj tshuaj tiv thaiv thib ob?
Cov tshuaj tiv thaiv COVID-19 thib ob yog dab tsi? Cov kev mob tshwm sim feem ntau tom qab koob thib ob yog qhov mob ntawm qhov chaw txhaj tshuaj (92.1% tshaj tawm tias nws kav ntev dua 2 teev); qaug zog (66.4%); mob lub cev lossis leeg nqaij (64.
Puas muaj cov dej tsis huv rau kev txhaj tshuaj rau kev siv tshuaj?
dej tsis huv rau nqus tau. Cov dej no feem ntau yog npaj rau siv nrog inhalators thiab npaj cov tshuaj inhalation. Nws nqa cov ntsiab lus nruj me ntsis rau cov kab mob endotoxins ntau dua li tsis muaj WFI thiab, yog li ntawd, tsis haum rau kev siv parenteral.
Koj puas tuaj yeem ntes mumps yog tias txhaj tshuaj?
Txawm li cas los xij, qee cov neeg uas tau txais ob koob tshuaj MMR tseem tuaj yeem kis tau tus kab mob qog, tshwj xeeb tshaj yog tias lawv tau ntev, nyob ze nrog tus neeg muaj tus kabmob. Yog tias tus neeg tau txhaj tshuaj tiv thaiv kab mob qog, lawv yuav muaj mob tsawg dua li tus neeg tsis tau txhaj tshuaj.
Yuav ua li cas txhaj tshuaj tiv thaiv kab mob hauv qab no niaj hnub muab tshuaj intramuscularly?
Nyob, cov tshuaj tiv thaiv tsis zoo (piv txwv li, MMR, varicella, daj kub taub hau) thiab qee yam tshuaj tiv thaiv tsis ua haujlwm (xws li meningococcal polysaccharide) tau pom zoo los ntawm cov tuam txhab ua haujlwm los ntawm subcutaneous. txhaj tshuaj.
Puas yuav ua rau kom nqus tau cov tshuaj txhaj tshuaj intramuscularly?
Kev nqus sai sai rau kev txhaj tshuaj intramuscular piv rau kev txhaj tshuaj subcutaneous. Qhov no yog vim cov leeg nqaij muaj ntshav ntau dua li thaj chaw hauv qab ntawm daim tawv nqaij. Cov nqaij mos kuj tseem tuaj yeem tuav cov tshuaj ntau dua li cov ntaub so ntswg subcutaneous.
