Babylonian computation of the square root of 2
YBC 7289 is a Babylonian clay tablet notable for containing an accurate sexagesimal approximation to the square root of 2, the length of the diagonal of a unit square. This number is given to the equivalent of six decimal digits, "the greatest known computational accuracy ... in the ancient world". The tablet is believed to be the work of a student in southern Mesopotamia from some time in the range from 1800–1600 BC, and was donated to the Yale Babylonian Collection by J. P. Morgan.