Question

Is it ever possible for the domain and range in a function to have different numbers of entries (for example, 3 domain entries to 5 range entries, or 2 range entries to 7 domain entries)? What happens when this is the case?

Answer 1

no. of entries in range cannot b more than in domain.....rest is all ok

Answer 2

Yes.
In a function, you can't have any element of the domain used more than once, but any number of the elements of the domain may be mapped to the same element of the range.

For example:

This is a function: {(1, 2), (2, 3), (3, 4)}
Domain: {1, 2, 3} Range: {2, 3, 4}

This is not a function: {(1, 2), (1, 3) }
Domain: {1} Range {2, 3}

This is a function: {(1, 2), (2, 2), (3, 2)}
Domain {1, 2, 3} Range: {2}