The word "surjection" is spelled with the letters S-U-R-J-E-C-T-I-O-N. According to IPA phonetic transcription, the first syllable is pronounced as "sɜːr", which is similar to "sir" with a longer 'r' sound. The second syllable is pronounced as "dʒɛk", which sounds like "jek" with a 'd' sound at the beginning. The last syllable is pronounced as "ʃən", which sounds like "shun" with a neutral vowel sound. "Surjection" is a term used in mathematics to describe a function that maps one set onto another.
A surjection, in mathematics, refers to a concept in the field of set theory and functions. It is a term used to describe a particular type of mapping or function between two sets. More precisely, a surjection is a function that has the property of covering or mapping the entire range of the target set.
To understand this definition, we need to explore the components of a surjection. First, let us consider two sets: the domain and the codomain. The domain represents the set of input elements, while the codomain represents the set of possible output elements.
A surjection is then defined as a mapping or function that assigns each element of the domain to a unique element in the codomain, ensuring that every element in the codomain has at least one corresponding element in the domain. In simpler terms, a surjection is a function where no element in the target set is left unmapped or uncovered.
In practical terms, imagine a surjection as a "covering" function where all the values from the codomain are reached or "hit" by at least one element from the domain. It can be visualized as an onto mapping, ensuring that no element of the target set is left untouched.
Surjections play a crucial role in various mathematical fields, such as algebra, analysis, and topology, as they allow for the study and analysis of functions that fully cover target sets. They provide a fundamental tool for understanding and analyzing many mathematical structures and functions.
The word "surjection" has its origin in mathematics, specifically in the field of set theory and function theory. It is derived from the French word "surjection", which can be further broken down into two components: "sur", meaning "above" or "on", and "jection", derived from the French verb "jeter", meaning "to throw".
In mathematics, a "surjection" refers to a function between two sets where every element in the target set has at least one pre-image in the domain set. The concept of surjection was introduced by the French mathematician André Weil in the mid-20th century, and the name reflects the idea of mapping or throwing elements from the domain set onto the target set.
Over time, the term "surjection" has become widely used in mathematics to describe such functions that cover the entire target set, leading to its incorporation into mathematical terminology in various languages, including English.