Understanding Domain of Functions

What is the domain of a function with a fraction where the denominator is x(x-4)?

• (-∞, 4) ∪ (4, ∞)

• (-∞, 0) ∪ (0, ∞)

• (-∞, 0) ∪ (0, 4) ∪ (4, ∞)

• (0, 4)

How do you determine the domain of a function with a square root?

• Set the expression under the square root to be equal to zero

• Set the expression under the square root to be greater than or equal to zero

• Set the expression under the square root to be greater than zero

• Set the expression under the square root to be less than zero

For a function with a square root in the denominator, what must be true about the expression under the square root?

• It can be any real number

• It must be equal to zero

• It must be less than zero

• It must be greater than zero

In a function with both a fraction and a square root, what is a key consideration for the domain?

• The numerator must be zero

• The denominator must not be zero and the expression under the square root must be non-negative

• The expression under the square root must be negative

• The denominator must be zero

When solving inequalities for domain, what happens to the inequality sign when you multiply or divide by a negative number?

• It becomes undefined

• It becomes an equality

• It changes direction

• It stays the same