ellipse yog ib daim duab geometric tau los ntawm lawv cov voj voog los ntawm kev hloov pauv affine.
Cov ntsiab lus
Cov qauv hauv cheeb tsam
Qhov cheeb tsam ntawm ib qho ellipse (S) yog sib npaug rau cov khoom ntawm qhov ntev ntawm nws cov semiaxes thiab tus lej π:
S = Cov π *a* ib
Nco ntsoov: rau xam tus nqi ntawm tus lej π sib npaug rau 3,14.
Piv txwv ntawm qhov teeb meem
Nrhiav thaj tsam ntawm ib qho ellipse yog tias nws cov semiaxes yog 2 cm thiab 4 cm.
Kev txiav txim siab:
Peb hloov cov ntaub ntawv paub rau peb raws li cov xwm txheej ntawm qhov teeb meem rau hauv cov qauv: S u3,14d 2 * 4 cm * 25,12 cm uXNUMXd XNUMX cm2.