What is the domain of the following relation?

[tex] \{(1,2), (4,-5), (-3,1), (1,3)\} [/tex]

A. [tex] \{-5,-3,1,2,3,4\} [/tex]

B. [tex] \{1,3,4\} [/tex]

C. [tex] \{-3,1,4\} [/tex]

D. [tex] \{-5,1,2,3\} [/tex]



Answer :

To determine the domain of a given relation, we need to examine the set of first elements in each ordered pair within the relation.

The given relation is:
[tex]\[ \{(1, 2), (4, -5), (-3, 1), (1, 3)\} \][/tex]

1. Look at each ordered pair in the relation:
- For [tex]\((1, 2)\)[/tex], the first element is [tex]\(1\)[/tex].
- For [tex]\((4, -5)\)[/tex], the first element is [tex]\(4\)[/tex].
- For [tex]\((-3, 1)\)[/tex], the first element is [tex]\(-3\)[/tex].
- For [tex]\((1, 3)\)[/tex], the first element is [tex]\(1\)[/tex].

2. Collect all unique first elements from these pairs:
[tex]\[ \{1, 4, -3\} \][/tex]

Hence, the domain of the given relation [tex]\(\{(1, 2), (4, -5), (-3, 1), (1, 3)\}\)[/tex] is [tex]\(\{1, 4, -3\}\)[/tex].

We now compare this with the given options:
- Option A: [tex]\(\{-5, -3, 1, 2, 3, 4\}\)[/tex]
- Option B: [tex]\(\{1, 3, 4\}\)[/tex]
- Option C: \{-3, 1, 4\}\)
- Option D: [tex]\(\{-5, 1, 2, 3\}\)[/tex]

The correct domain from these options is:
[tex]\[ C: \{-3, 1, 4\} \][/tex]

Therefore, the domain of the relation is the set [tex]\(\{-3, 1, 4\}\)[/tex], which corresponds to Option C.