What is the domain and range of #f(x) = -x/2#?

1 Answer
Oct 20, 2017

Answer:

#x in RR# and #f(x) in RR#
OR
#x in (-oo,+oo)# and #f(x) in (-oo,+oo)#

Explanation:

The domain is the set of all possible #x#-values which will make the function "work", and will output real #f(x)#-values.

So when we have the function #f(x)=-x/2# we can let #x# be any real number and we will always get a real and defined value of #f(x)#.
Therefore the domain is #RR#.

The range is the resulting #f(x)#-values we get after substituting all the possible #x#-values.

Here too, all the possible values of #f(x)# are all the real numbers.
Therefore the range is also #RR#.

Example -->

Let #x=sqrt2# which is a real number.
then we'd get #f(x)=-sqrt2/2# which is also a real number.