What is the domain of #{(1,2),(2,6),(3,5),(4,6),(5,2)}#?

2 Answers
Sep 9, 2015

Domain is #{1, 2, 3, 4, 5}#

Explanation:

For a collection of discrete pairs #(color(red)(x),color(blue)(f(x))) in {"some collection of ordered pairs"}#

  • The Domain is the collection of #color(red)(x)# values
  • The Range is the collection of #color(blue)(f(x))# values

#(color(red)(x),color(blue)(f(x))) in {(color(red)(1),color(blue)(2)), (color(red)(2),color(blue)(6)), (color(red)(3),color(blue)(5)), (color(red)(4),color(blue)(6)), (color(red)(5),color(blue)(2))}#

Sep 9, 2015

The domain is {1,2,3,4,5}

Explanation:

The domain of a relation or a function is the set of all first elements in an ordered pair that is in the function.

With the usual naming of pairs as #(x,y)#, the domain is the collection (set) of all #x# values.

In notation, the domain of a relation or function #bb"R"# is:

#{x|(EEy)((x,y)in bb"R")}#