Video: Cov khoom dot txhais li cas?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Hauv lej, the dot khoom los yog khoom scalar yog ib qho kev ua algebraic uas siv ob qhov sib npaug ntawm qhov sib npaug ntawm cov lej (feem ntau ua haujlwm vectors) thiab xa rov qab ib tus lej. Geometrically, nws yog khoom ntawm Euclidean qhov loj ntawm ob lub vectors thiab cosine ntawm lub kaum sab xis ntawm lawv.
Tom qab ntawd, nws txhais li cas yog tias cov khoom dot yog 1?
1 . Tus nqi ntawm cov dot khoom muaj qhov ntev square ntev, yog li nws txhais tau tias tsis muaj ib yam dab tsi uas tsis muaj ib khub ntawm qhov ntev los muab piv rau (xws li qhov ntev ntawm qhov qub vectors) tshwj tsis yog nws yog xoom, vim hais tias cov lus no ua tsis nyob ntawm qhov kev xaiv ntawm units.
Tsis tas li ntawd, nws txhais li cas thaum cov khoom lag luam zoo lossis tsis zoo? Hais lus dav dav, yog tias dot khoom ntawm ob tsis-zero vectors yog zoo , ces ob vectors taw tes rau tib qho kev taw qhia, lub ntsiab lus qis dua 90 degrees. Yog tias dot khoom yog tsis zoo , tom qab ntawd ob lub vectors taw qhia nyob rau hauv qhov sib txawv, lossis siab dua 90 thiab tsawg dua lossis sib npaug rau 180 degrees.
Ib yam li ntawd, lub hom phiaj ntawm cov khoom dot yog dab tsi?
Cov dot khoom yog tus nqi qhia txog kev sib raug zoo ntawm ob lub vectors.
Dot khoom piv txwv yog dab tsi?
Piv txwv : laim Dot Khoom for: a·b = |a| × |b| x cos(θ) a·b = |a| × |b| x cos(90°) a· b = |a| × |b| IB = 0.
Pom zoo:
Dab tsi yog cov khoom ntawm dot khoom?
Cov khoom dot ua tiav cov khoom nram qab no yog tias a, b, thiab c yog cov vectors tiag tiag thiab r yog scalar. Commutative: uas ua raws li lub ntsiab lus (θ yog lub kaum sab xis ntawm a thiab b): Distributive tshaj vector ntxiv: Bilinear: Scalar multiplication:
Cov khoom twg yog cov piv txwv ntawm cov khoom siv tshuaj xyuas txhua yam uas siv?
Piv txwv ntawm cov khoom siv tshuaj muaj xws li flammability, toxicity, acidity, reactivity (ntau hom), thiab kub ntawm combustion. Hlau, piv txwv li, ua ke nrog oxygen nyob rau hauv lub xub ntiag ntawm dej los ua xeb; chromium tsis oxidize (Daim duab 2)
Yuav ua li cas cov khoom siv caj ces hauv txhua lub xov tooj tshiab tsim los ntawm kev faib tawm ntawm tes sib piv nrog cov khoom siv caj ces hauv lub xov tooj qub?
Mitosis tshwm sim nyob rau hauv ob lub nuclei uas zoo tib yam rau thawj nucleus. Yog li, ob lub hlwb tshiab tsim tom qab kev faib tawm ntawm tes muaj tib yam khoom siv caj ces. Thaum lub sij hawm mitosis, chromosomes condense los ntawm chromatin. Thaum saib nrog lub microscope, chromosomes pom nyob rau hauv lub nucleus
Cov khoom ua haujlwm ntawm cov zaub mov txhais li cas?
Cov khoom ua haujlwm piav qhia txog cov khoom xyaw coj li cas thaum npaj thiab ua noj, lawv cuam tshuam li cas cov khoom noj tiav raws li nws zoo li, saj, thiab xav tau
Dot khoom txhais li cas?
Hauv kev ua lej, cov khoom dot lossis cov khoom lag luam scalar yog kev ua haujlwm algebraic uas siv ob qhov sib npaug ntawm cov lej (feem ntau ua haujlwm vectors) thiab xa rov qab ib tus lej. Geometrically, nws yog cov khoom ntawm Euclidean magnitudes ntawm ob vectors thiab cosine ntawm lub kaum sab xis ntawm lawv