3 Txoj Hauv Kev Nrhiav Qhov Siab ntawm Ib Daim Duab Peb Hlis

Cov txheej txheem:

3 Txoj Hauv Kev Nrhiav Qhov Siab ntawm Ib Daim Duab Peb Hlis
3 Txoj Hauv Kev Nrhiav Qhov Siab ntawm Ib Daim Duab Peb Hlis

Video: 3 Txoj Hauv Kev Nrhiav Qhov Siab ntawm Ib Daim Duab Peb Hlis

Video: 3 Txoj Hauv Kev Nrhiav Qhov Siab ntawm Ib Daim Duab Peb Hlis
Video: hlub tsis khuv xim txoj sia Part 3 2024, Lub peb hlis ntuj
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Txhawm rau xam thaj tsam ntawm daim duab peb sab, koj yuav tsum paub nws qhov siab. Yog tias cov ntaub ntawv no tsis muab rau hauv qhov teeb meem, nws yooj yim los suav nws raws li qhov koj twb paub lawm! Kab lus no yuav qhia koj ob txoj hauv kev sib txawv kom nrhiav tau qhov siab ntawm daim duab peb sab, nyob ntawm seb cov ntaub ntawv twg koj tau muab.

cov kauj ruam

Txoj Kev 1 ntawm 3: Siv Lub Hauv Paus thiab Cheeb Tsam txhawm rau Nrhiav Qhov Siab

Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 1
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 1

Kauj Ruam 1. Nco qab cov mis rau nrhiav thaj tsam ntawm daim duab peb sab

Nws yog sawv cev los ntawm A = h IB.

  • LUB = thaj tsam ntawm daim duab peb sab.
  • B = ntev ntawm daim duab peb sab puag.
  • H = qhov siab ntawm lub hauv paus ntawm daim duab peb sab.
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 2
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 2

Kauj Ruam 2. Saib daim duab peb sab thiab txiav txim siab qhov twg tuaj yeem hloov pauv

Hauv qhov no, koj twb paub thaj chaw tus nqi, yog li koj tuaj yeem siv nws los txheeb xyuas LUB. Koj kuj yuav tsum paub qhov ntev npaum li cas ntawm ib sab; teeb tus nqi no rau B. Yog tias koj tsis paub thaj tsam thiab ntev ntawm ib sab, koj yuav tau siv lwm txoj hauv kev.

  • Txhua sab ntawm daim duab peb sab tuaj yeem yog lub hauv paus, tsis muaj teeb meem li cas nws tau kos. Txhawm rau pom lub tswv yim no, xav txog qhov tig daim duab peb sab kom txog thaum paub sab ntev yog hauv qab.
  • Piv txwv li, yog tias koj paub tias thaj tsam ntawm daim duab peb sab sib npaug li 20, thiab ib qho ntawm nws sab yog 4, ces: A = 20 hli thiab b = 4 hli.
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 3
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 3

Kauj Ruam 3. Nkag mus rau qhov tseem ceeb hauv kab zauv A = ½ bh thiab ua cov lej

Ua ntej, sib npaug ntawm lub hauv paus (B) los ntawm ½ thiab tom qab ntawd faib thaj tsam (LUB) rau qhov khoom. Qhov txiaj ntsig tshwm sim yuav sawv cev qhov siab ntawm daim duab peb sab!

  • Hauv peb qhov piv txwv: 20 = ½ (4) h
  • 20 = 2 teev
  • 10 = hli

Txoj Kev 2 ntawm 3: Nrhiav Qhov Siab ntawm Ib Daim Duab Peb Hlis

Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 4
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 4

Kauj Ruam 1. Nco qab cov khoom ntawm daim duab peb sab

Ib daim duab peb sab sib npaug muaj peb sab sib npaug thiab peb lub kaum sib npaug, 60 degrees txhua. Yog tias koj txiav nws ib nrab, muaj ob txoj kab sib dhos sab xis uas zoo sib xws.

Hauv qhov piv txwv no, peb yuav siv daim duab peb sab sib npaug nrog 8-gauge sab

Nrhiav qhov siab ntawm daim duab peb sab 5
Nrhiav qhov siab ntawm daim duab peb sab 5

Kauj Ruam 2. Rov nco txog Pythagorean Theorem

Pythagoras 'theorem hais tias rau txhua txoj cai peb tog nrog ntsuas ob txhais ceg Cov thiab B thiab ntev hypotenuse ç, Cov2 + b2 = c. Peb tuaj yeem siv qhov sib npaug no los xam qhov siab ntawm peb daim duab peb sab equilateral.

Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 6
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 6

Kauj Ruam 3. Sib faib daim duab peb sab sib npaug hauv ib nrab thiab teeb tsa qhov tseem ceeb rau qhov sib txawv a, b, thiab c

cov hypotenuse ç yuav sib npaug rau thawj sab ntev. lub collared Cov yuav muaj kev ntsuas sib npaug ½ ntawm sab ntev thiab sab B sawv cev qhov siab ntawm daim duab peb sab peb xav pom.

Siv daim duab peb sab sib npaug los ntawm peb tus piv txwv, nrog rau sab ntsuas 8, c = 8 hli thiab ib = 4.

Nrhiav qhov siab ntawm daim duab peb sab Step 7
Nrhiav qhov siab ntawm daim duab peb sab Step 7

Kauj Ruam 4. Nkag mus rau qhov tseem ceeb hauv Pythagorean theorem thiab nrhiav tus nqi b2.

Ua ntej, nce ç thiab Cov, muab txhua tus lej los ntawm nws tus kheej. Tom qab ntawd rho tawm Cov2 nyob rau hauv ç2.

  • 42 + b2 = 82
  • 16+ib2 = 64
  • B2 = 48
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 8
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 8

Kauj Ruam 5. Nrhiav lub hauv paus cag ntawm b2 kom tau qhov siab ntawm daim duab peb sab.

Siv cov hauv paus plaub fab ua haujlwm hauv lub laij lej txhawm rau nrhiav tus nqi ntawm b2. Cov lus teb yuav yog qhov siab ntawm daim duab peb sab.

b = √b (48) = 6, 93

Txoj Kev 3 ntawm 3: Txiav txim siab Qhov Siab nrog Lub Ntsej Muag thiab Ib Sab

Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 9
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 9

Kauj Ruam 1. Txiav txim siab paub qhov txawv txav twg

Koj tuaj yeem pom qhov siab ntawm daim duab peb sab thaum koj paub qhov tseem ceeb ntawm cov ces kaum thiab ib sab yog tias lub kaum sab xis yog nruab nrab ntawm lub hauv paus thiab sab nyob rau hauv nqe lus nug, lossis tag nrho peb qhov siab. Peb yuav hu ob sab ntawm daim duab peb sab a, b thiab c, thiab cov ces kaum A, B thiab C.

  • Yog tias koj paub tus nqi ntawm peb sab, koj tuaj yeem siv Heron tus qauv thiab cov mis rau thaj tsam ntawm daim duab peb sab.
  • Yog tias koj paub tus nqi ntawm ob sab thiab lub kaum ntse ntse, koj yuav tsum siv tus qauv rau thaj tsam kom paub qhov txiaj ntsig ntawm ob lub kaum thiab sab ntxiv. A = ½ ab (sin C).
Nrhiav qhov siab ntawm daim duab peb sab Step 10
Nrhiav qhov siab ntawm daim duab peb sab Step 10

Kauj Ruam 2. Siv Heron tus qauv yog tias koj paub tus nqi ntawm peb sab

Qhov sib npaug no muaj ob ntu. Ua ntej, koj yuav tsum pom qhov sib txawv s, uas yog sib npaug ib nrab ntawm ib puag ncig ntawm daim duab peb sab. Qhov no yog ua tiav siv cov qauv hauv qab no: s = (a+b+c) / 2.

  • Yog li, rau daim duab peb sab nrog a = 4, b = 3 thiab c = 5, s = (4+3+5) / 2. Raws li qhov tshwm sim, peb muaj s = (12) / 2 = 6.
  • Tom qab ntawd koj tuaj yeem siv ntu thib ob ntawm Heron tus lej: Cheeb Tsam = √ [s (y-a) (y-b) (y-c)]. Hloov Cheeb Tsam nrog nws cov nqi sib npaug hauv cov lej rau thaj tsam ntawm daim duab peb sab: ½ bh (lossis ½ ah lossis ½ ch).
  • Ua cov laij lej txhawm rau nrhiav tus nqi h. Hauv daim duab peb sab hauv peb qhov piv txwv, nws yuav zoo li no: ½ (3) h = √ [6 (6-4) (6-3) (6-5)]. Raws li qhov tshwm sim, peb muaj 3/2 h = √ [6 (2) (3) (1)] = √ [36]. Siv lub laij lej los nrhiav lub hauv paus cag ntawm tus nqi no, uas hauv qhov no yog sib npaug rau 3/2 h = 6. Yog li qhov siab yuav muaj qhov ntsuas sib npaug rau 4 yog tias peb siv sab b ua lub hauv paus.
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 11
Nrhiav qhov siab ntawm daim duab peb sab Kauj Ruam 11

Kauj Ruam 3. Yog tias koj paub tus nqi ntawm ib sab thiab lub kaum ntse ntse, siv qhov sib npaug rau thaj tsam uas muaj ob sab thiab kaum sab xis

Hloov thaj tsam tus nqi nrog nws sib npaug hauv cov mis rau thaj tsam ntawm daim duab peb sab: ½ bh. Qhov no yuav muab koj cov qauv zoo ib yam rau ½ bh = ½ ab (sin C). Nws tuaj yeem ua kom yooj yim rau h = a (kev txhaum C), yog li tshem tawm ib qho ntawm cov kev hloov pauv piv rau ob sab.

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