Decades: 1180s 1190s 1200s 1210s 1220s - 1230s - 1240s 1250s 1260s 1270s 1280s
Years: 1232 1233 1234 1235 1236 - 1237 - 1238 1239 1240 1241 1242
Births
Deaths
... terms of the coefficients 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 ...