SFERA

SFYORA (az yunonisfaira—kura), hamvorii sarbastaero guyand, ki hamai nuqtahoyashon az yak nuqta (mar kazi Sfera) dar yak khel masofa voqeand. Parchaero, ki markaz va nuqtai dilkhohi Sferaro mepayvandad (inchunin darozii on porcharo), radiusi Sfera menomand. Masohati SferaS = 4R² meboshad (R — radiusi Sfera). Qismi fazoe, ki bo Sfera mahdud buda, markazi onro niz dar bar megirad, kura nom dorad; hajmi kuraV=³meboshad.  Az napari geometriyai tahlili Sfera hamvorii tartibi duyumest, ki muodilaash dar sistemai koordinatahoi rostkunja chunin ast:

(kh – a)² + (u – b)² + (z – s)² = R² (a, b, s — koordinatahoi Sfera).