Question

2) what is the domain of f(x) = x³ + 6x² + 5

Answer 1

`-\infty \: < x < \infty`

or, in interval notation as

`\left(-\infty \:,\:\infty \:\right)`

Explanation:

The domain of a function
`f(x)` is the set of all values of
`x` for which
`f(x)` is real and defined

The given function is f(x) = x³ + 6x² + 5

There are no undefined points. So the domain is the set of all real numbers that can be expresses as


`-\infty \: < x < \infty`

or, in interval notation


`\left(-\infty \:,\:\infty \:\right)`