Question

What are the domain and range of f(x) = 4x – 8? A. domain: {x | x is a real number}; range: {y | y > –8} B. domain: {x | x is a real number}; range: {y | y > 8} C. domain: {x | x > 4}; range: {y | y > –8} D. domain: {x | x > –4}; range: {y | y > 8}

Answer 1

Answer: Non of the options is correct.

Step-by-step explanation:

Domain of a function are the minimum and maximum values of independent variable (x).

You are given the function:

f(x) = 4x – 8

The domain can be any real numbers.

Range is the minimum to maximum value of dependent variable ( y )

From the given equation:

f(x) = 4x – 8

If the value of domain are substituted, the range will also be any real numbers.

Non of the answers is correct because both the domain and the range are all real numbers.

But the best option among the given option is option A:

domain: {x | x is a real number}; range: {y | y > –8}