What is the domain and range of #y = x + 3 #?

1 Answer
Rafael
Feb 27, 2016

#domf=RR#
#ranf=RR#

Explanation:

#f(x)=x+3#

Domain

Is there any value of #x# that will make #f(x)# undefined?

The answer to this is no, so the domain is the set of all real numbers #RR#.

#domf=RR#

Range

You will notice that the graph of #x+3# is just a line, meaning it will intersect all values of #y# (since it increases and decreases without limit).

Therefore, the range is also the set of all real numbers #RR#.

#ranf=RR#

Just keep this in mind. When you're given a linear function, its domain and range are both the set of all real numbers (unless the problem tells you it isn't).

Related questions
See all questions in Domain and Range of a Function
Impact of this question
1944 views around the world
You can reuse this answer
Creative Commons License