Question

Give the domain and range of the relation

x y
1 1
4 4
8 1
Domain {1,1} Range {4,4}
Domain {1,4,8} Range {1,4}
Domain {1,4} Range {1,4,8}
Domain {4,4} Range {8,1}

Answer 1

OPTION B:

Domain: {1, 4, 8}

Range: {1, 4}

Explanation:

Domain of a function is the set of all elements that is mapped to an element on the co - domain.

The co - ordinates of the given function are:

`$ (1, 1); (4, 4); (8, 1) $`

1 is mapped to 1.

4 is mapped to 4.

8 is mapped to 1.

This means, the elements {1, 4, 8} will form the domain.

The range is a subset of the co - domain, which have a pre - image.

Here, Co - domain = Range.

Hence, Range = {1, 4}

It is enough to represent the element only once.

Hence, OPTION B is the answer.