Cov txheej txheem:

Qhov chaw ntawm lub cardioid yog dab tsi?
Qhov chaw ntawm lub cardioid yog dab tsi?

Video: Qhov chaw ntawm lub cardioid yog dab tsi?

Video: Qhov chaw ntawm lub cardioid yog dab tsi?
Video: Yog hmoov dab tsi - Gao Nou Kue ft. Mang Vang (Official Music Video) New song 2020 2024, Kaum ib hlis
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Nrhiav tus cheeb tsam hauv cov cardioid r = 1 + cos θ. Teb: Cov cardioid yog li lub npe vim nws lub plawv zoo li tus. Siv cov kab txaij radial, qhov txwv ntawm kev sib koom ua ke yog (sab hauv) r ntawm 0 txog 1 + cos θ; (sab nraud) θ ntawm 0 txog 2π. Yog li, cov cheeb tsam yog. 2π 1+cos θ dA = r dr dθ.

Ntxiv mus, koj ua li cas nrhiav thaj tsam ntawm thaj tsam polar?

Lub cheeb tsam ntawm ib cheeb tsam hauv polar coordinates txhais los ntawm qhov sib npaug r = f (θ) nrog α≦θ≦β yog muab los ntawm qhov tseem ceeb A = 1 2 ∫βα[f(θ)] 2 d θ. Txhawm rau nrhiav thaj chaw nruab nrab ob curves nyob rau hauv lub polar coordinate system, ua ntej nrhiav cov ntsiab lus ntawm kev sib tshuam, ces rho tawm cov chaw sib thooj.

Ib tug kuj yuav nug, ua li cas koj integrate Cos 2x? Cov ib qho ntawm cos ( 2x ib ) yog (1/2) sin( 2x ib ) + C, qhov C yog qhov tsis tu ncua.

Ntawm no, dab tsi yog tus qauv rau cheeb tsam hauv qab nkhaus?

Cov cheeb tsam nyob rau hauv ib tug nkhaus nruab nrab ntawm ob lub ntsiab lus yog pom los ntawm kev ua ib qho tseem ceeb ntawm ob lub ntsiab lus. Yuav nrhiav tau thaj tsam hauv qab tus nkhaus y = f(x) nruab nrab ntawm x = a & x = b, integrate y = f(x) nruab nrab ntawm qhov txwv ntawm a thiab b. Qhov no cheeb tsam tuaj yeem suav nrog kev sib koom ua ke nrog cov kev txwv muab.

Yuav ua li cas koj daws parametric equations?

Piv txwv 1:

  1. Nrhiav ib txheej ntawm parametric sib npaug rau qhov sib npaug y = x2 + 5.
  2. Muab ib qho ntawm qhov sib txawv sib npaug rau t. (hais x = t).
  3. Tom qab ntawd, qhov sib npaug muab tau rov sau dua li y = t2 + 5.
  4. Yog li ntawd, ib txheej ntawm parametric equations yog x = t thiab y = t2 + 5.

Pom zoo: