Decades: 1220s 1230s 1240s 1250s 1260s - 1270s - 1280s 1290s 1300s 1310s 1320s
Years: 1273 1274 1275 1276 1277 - 1278 - 1279 1280 1281 1282 1283
Births
Deaths
... a, b and c, which are assumed to be real (but see below for generalizations) with a being non-zero. These solutions are also called the roots of the equation. The formul ...