How to find domain for #f(x) = x^2+3#?

1 Answer
Oct 7, 2015

Answer:

The domain is the whole set #\mathbb{R}#.

Explanation:

The domain of a function is the set of value you can give as input to the function. Now, your function takes a number #x#, squares it (#x^2#), and then adds #3#: (#x^2+3#).

The question is: is there any number which can't be squared? And the answer is no: we can square any real number, since it is always a legit operation. Needless to say, we can also always add #3# to any number. So, there are no numbers to exclude from the domain.