Okirikiri olu usoro ihe mgbako

Tinye na okirikiri nke a okirikiri:

Okirikiri bụ a n'ụzọ zuru okè gburugburu geometrical ihe na atọ akụkụ ohere nke na-elu nke a kpam kpam gburugburu bọl. A okirikiri a kọwarala mathematically dị ka set nke ihe niile dị ya mgbe otu anya r si a nyere ebe.

Formula maka olu nke a okirikiri: ,
R - dịpụrụ adịpụ ruo nke a okirikiri