lecture 5 - relations and functions Flashcards
1
Q
A binary relation
A
A set of ordered pairs
2
Q
Domain and subdomain of R
A
Domain: The range of x values
subdomain: The range of y values
3
Q
The cartesian product
A
The product of all sets together
4
Q
what is a function ?
A
A binary relation between the input and output
5
Q
what is a partial function?
A
Is when not the whole domain is used
6
Q
When is a function subjective?
A
when every element of the codomain is “hit” by at least one element in the domain
7
Q
what is an infective function?
A
when no two elements from the domain meet at a single element in the codomain
8
Q
what is a function that’s both an infection and surjection called?
A
bijection
