What is the domain and range of #y=x^2+3#?

1 Answer
Sep 7, 2015

Domain is #RR#

Range is #<3;+oo)#

Explanation:

Domain of a function is a subset of #RR# where function value can be calculated. In this example there are no limitations for #x#. They would appear if there was for example a square root or if #x# was in the denominator.

To calculate the range you have to analyse the graph of a function:

graph{(y-x^2-3)(x^2+(y-3)^2-0.04)=0 [-8.6, 9.18, -0.804, 8.08]}

From this graph you can easily see, that the function takes all values greater han or equal to #3#.