Abu Omar Baghdadi
Tuesday, 01 April 2008
Al-Baghdadi is Abu MansurAbr Al-Qahir ibn Tahir ibn Muhammad ibn Abdallah Al-Tamini Al-Shaffi Al-Baghdadi (980-1037) is known as Ibn Tahir,.. In Asfirayin, Al-Baghdadi taught for many years in the mosque on several subjects whilst never taking any payment. Although he was one of the greatest theologians of his age and many works are attributed to him, none has been studied scientifically. Here we look at two of his mathematical works.
The first book is a small treatise on mensuration: Kitab fi'l-misaha, which gives the units of length, area and volume and ordinary mensuration rules. The second treatise, Al-Takmila fi'l-Hisab, is a work in which Al-Baghdadi notes in the introduction that earlier works are either too brief to be of great use or are concerned with only one chapter (system) of arithmetic. In this work, therefore, he seeks to explain all kinds of arithmetic in use.
Several important results in number theory appear in the Al-Takmila as do comments which allow us to obtain information on certain texts of Al-Khwarizmi which are now lost. In Al-Takmila, Al-Baghdadi gives an interesting discussion of abundant numbers, deficient numbers, perfect numbers and equivalent numbers.
The last of Al-Baghdadi's seven systems, business arithmetic, begins with business problems and ends with two chapters on curiosities that would find a place in any modern book on recreational problems or the modulo principle. One example is provided here: your partner thinks of a number not greater than 105. He casts out fives* and is left with a; he casts out sevens and he is left with b; he casts out threes and is left with c; Calculate 21a+ 15b+ 70c; cast out 105's, and the residue is the number
| < Prev | Next > |
|---|