Kwezinye kwezine i cosine ye-HIV? Kwezinye kwezine sine kunye cosine ye-HIV?

Imibuzo evela nasekufundweni kwemisebenzi netrigonometri zahlukahlukene. Abanye babo - ukuba yokuhlala zoluntu cosine akhabayo kunye navumelanayo, kwezinye iikota sine akhabayo kunye navumelanayo. Yonke into lula ukuba uyazi ukuba ukubala njani ixabiso le misebenzi ezimbombeni ezahlukeneyo kwaye uqhelene siseko ukwakhiwa imisebenzi kwitshati.

Yintoni i cosine

Ukuba sicinga unxantathu ekunene-engile egqithe, siye banolwahlulo ilandelayo esichaza ukuba: i cosine ye angela a lulwahlulo yomlenze ezikufutshane ukuya hypotenuse BC AB (Figure 1.): eKos a = BC / AB.

Ngoncedo unxantathu enye, unako ukufumana i sine ye ekujikeni, kodwa azikweli phezulu kunye elinekona ezisibhozo. Sinusitis lulwahlulo yomlenze malunga oluphezu izithethi ukuya hypotenuse AB. Kodwa azikweli phezulu le angle, ukuba engile wacela sine bahlulwe icosine kwinkalo enye; esikhundleni Ifomula ehambelana ekufumaneni i cosine kunye sine, sinokuyifumana ukuba kubatshaba- a = AC / BC. Elinekona ezisibhozo ke uguqulo lonikezelo lwe umsebenzi ilayini ezibambanayo kodwa azikweli, kuya kuba njalo; ctg a = BC / AC.

Oko kukuthi, kwafunyaniswa ukuba usoloko umnye kule ilungelo triangle umba ratio ngenxa amaxabiso efanayo ekujikeni. Bekuya kubonakala ukuba kucace ezi zithethe, kodwa kutheni na inani negative?

Ukuze wenze oku, cinga unxantathu ukuqhuba inkqubo we cartesian, apho kukho amaxabiso omabini angu akhabayo kunye navumelanayo.

Ngokucacileyo malunga ikota, apho eminye

Yintoni zika cartesian? Ukuba sithethe isithuba ezikumila kumacala mabini, kufuneka imigca wayalela ezimbini yendlela yokwenza imigca iwela kwindawo O - i x-axis (Ox) kunye y-axis (Oy). Ukusuka kwindawo O kwicala umgca ngqo abekwe amanani akhabayo, kodwa kwelinye icala - negative. Ukusuka oku, ekugqibeleni, kuxhomekeke ngqo, kuyo nayiphi na yokuhlala cosine yi-HIV, kwaye apho, ngokufanelekileyo, akukho.

kwikota yokuqala

Ukuba ubeka unxantathu lasekunene-engile egqithe kwikota yokuqala ⁽⁰ ukuya ^kwi-90), apho x-ezimanyeneyo y angafanele (inxalenye AO kunye Bo aphezu nezamazembe apho amaxabiso a uphawu "+"), ngoko isono, ukuba i cosine ye ezifanayo kuya kuba kweqanda, yaye abelwe ixabiso ngo "dibanisa." Kodwa kwenzeka ntoni xa uhambisa unxantathu kwikota yesibini (ukusuka ⁹⁰ ukuya ^180)?

kwikota yesibini

Siyabona ukuba umlenze y-axis JSC wafumana engenaxabiso. I cosine ye-engile ngoku Umlinganiselo kwicala thabatha kunye, ngoko ke ixabiso layo lokugqibela uba negative. Kubonakala ukuba iqondo ngayo ikota cosine liyavumelana ixhomekeke indawo unxantathu kwi nokulungelelanisa inkqubo we cartesian. Kwaye kulo mzekelo, i cosine ye-engile ufumana engenaxabiso. Kodwa akukho nto iye yatshintsha le sinus, ukuba ujongisise umqondiso indlela OB ekunene, oye wahlala kulo mzekelo nge uphawu lokwengeza. Ukushwankathela kwiikota ezimbini zokuqala.

Ukuze ufumanise ukuba yintoni yokuhlala cosine uluntu akhabayo kunye navumelanayo (kwakunye sinus kunye neminye imisebenzi netrigonometri), kufuneka sijonge ukuba yintoni na umqondiso eyabelwe enye okanye omnye umlenze. Kuba cosine ye-engile a ebaluleke umlenze AB, kuba sine - RH.

Kwikota yokuqala kude kuphela ukuba uphendule lo mbuzo: "Yintoni kwindawo yokuhlala sine kunye cosine HIV ngexesha elinye?". Khangela, ngoba ngeke nangoku lihambisana umqondiso imisebenzi emibini.

Emlenzeni kwikota yesibini JSC waqalisa ukuba esinentlawulo engenaxabiso, yaye ngaloo ndlela i cosine kakubi. Kuba lixabiso elingqinelanayo sinus igcinwe.

kwikota yesithathu

Ngoku zombini umlenze AB kunye OB wajika negative. Khumbula ubudlelwane kuba sine kunye cosine:

Cos a = AB / AB;

Ona = IVOTI / AB.

AB usoloko uphawu oluvumelanayo kule nokulungelelanisa inkqubo, kuba akukho sibhekiswe nayiphi na nemigca enqamleze esiqwini ka namaqela athile. Kodwa ke imilenze baba ezimbi, yaye ngoko ke isiphumo ukuba zombini imisebenzi, ezibi kakhulu, ngenxa yokuba ukuba enze uphinda-phindo okanye ulwahlulo kunye amanani, kuquka omnye kuphela uba 'thabatha' umqondiso, umphumo uya kuba uqhelene nale.

Isiphumo kweli thuba:

1) Kukweliphi kota cosine HIV? Kulo wokuqala ezintathu.

2) Kule kota sine-HIV? Yokuqala neyesibini bathathu.

Kwikota yesine (ukusuka ^malunga 270 ukuya ^malunga 360)

Apha umlenze ibuyise uphawu JSC "dibanisa", yaye ngaloo ndlela i cosine kakhulu.

Kuba kwimeko i sine usenguye "negative" kuba umlenze RH wahlala ngezantsi kwindawo yokuqala O.

iziphumo

Ukuze siyiqonde into yokuhlala cosine elihle, ezingakhiyo, njl, kufuneka ukuba ukhumbule ukuba umlinganiselo ukubala i cosine: ezikufutshane ukuya kwikona yomlenze bahlulwe hypotenuse. Abanye ootitshala sinikele khumbula: ukuba (osinus) = (a) yembombo. Ukuba uyalikhumbula "cheat 'eziya ngokuzenzekelayo ukuba sine - lulwahlulo yomlenze malunga ekujikeni, kwesa hypotenuse.

Khumbula, kuzo naziphi yokuhlala cosine uluntu akhabayo kunye navumelanayo kunzima kakhulu. Netrigonometri imisebenzi ezininzi, yaye zonke ixabiso labo. Kodwa, ngenxa yoko; ngokuba amaxabiso alungayo le sine - 1, 2-yesine ⁽⁰ ukuya ^180); ngokuba cosine ye-1,-yesine 4 (0 ukuya ^{malunga 90} ukusuka ^malunga 270 ukuya ^malunga 360). Xa kwiikota eziseleyo imisebenzi ichazwe nge thabatha.

Mhlawumbi omnye umntu uza kuba lula ukukhumbula apho uphawu lomfanekiso function.

Kuba sinus kunokubonwa ukuba ukususela kwiqanda ukuya 180 ^kwi kummango singaphezulu umgca isono (x) ixabiso, oko kuthetha ukuba umsebenzi yi-HIV. Kuba cosine ngokunjalo: in i cosine kwikota entle (umfanekiso 7), kwaye apho kubonakala ukuhamba elibi migca ngaphezulu nangaphantsi esqwini of cos (x). Ngenxa yoko, masikhumbule iindlela ezimbini ukufumanisa umqondiso imisebenzi sine, cosine:

1. isangqa nabona oyi alinganayo kwelinye (nangona, eneneni, akukho nokuba yintoni embindini esangqeni, kodwa textbooks kukukhokelela nje ngumzekelo; oku kube lula imbono, kodwa kwangaxeshanye, ngaphandle kokuba Akukhathaliseki, abantwana angangenwa udidekile).

2. Kulo mfanekiso, kuxhomekeka function (s) ukusuka ingxabano x njengoko nani lokugqibela.

Ne indlela yokuqala ziyalandeleka koko ukungena ixhomekeke, kwaye ndacacisa oku iinkcukacha ngasentla. KuMfanekiso 7, zakhiwa kule data kwakunye kunokwenzeka iguqulela umsebenzi yesiphumo kwaye znakoprinadlezhnost yayo.