Question

How do you find the domain of `f(x) = x^2 + 5`?

Answer 1

See below.

Explanation:

Ignoring the `5`, we know that `x^2` has a minimum value of `0`, which is achieved when `x=0`.

When `x` approaches `-oo`, the range remains real (it approaches `oo`).

When `x` approaches `oo`, the range remains real (it approaches `oo`).

Thus, the domain of this function is `(-oo,oo)`.