Ukuthola indawo ye-parallelepiped engunxande: ifomula nesibonelo

Kulolu shicilelo, sizocubungula ukuthi singabala kanjani indawo engaphezulu ye-parallelepiped engunxande futhi sihlaziye isibonelo sokuxazulula inkinga yokulungisa into ethile.

Ifomula yendawo

Indawo (S) yobuso be-cuboid ibalwa ngale ndlela elandelayo:

S = 2 (ab + bc + ac)

Ifomula itholakala kanje:

1. Ubuso be-parallelelepiped engunxande bungonxande, futhi ubuso obuphambene buyalingana:
   • izisekelo ezimbili: ezinezinhlangothi a и b;
   • ubuso obunezinhlangothi ezine: nohlangothi a/b futhi mude c.
2. Ukwengeza izindawo zabo bonke ubuso, ngayinye elingana nomkhiqizo wezinhlangothi zobude obuhlukene, sithola: S = ab + ab + bc + bc + ac + ac = 2 (ab + bc + ac).

Isibonelo senkinga

Bala indawo engaphezulu ye-cuboid uma kwaziwa ukuthi ubude bayo buyi-6 cm, ububanzi buyi-4 cm, nobude bungu-7 cm.

Isinqumo:

Masisebenzise ifomula engenhla, sishintshe amanani aziwayo kuwo:

S = 2 ⋅ (6 cm ⋅ 4 cm + 6 cm ⋅ 7 cm + 4 cm ⋅ 7 cm) = 188 cm².