Questions: For the given functions f and g, complete parts (a)-(h). For parts (a)-(d), also find the domain.
f(x)=x-8 ; g(x)=2x^2
What is the domain of f-g? Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The domain is x .
(Use integers or fractions for any numbers in the expression. Use a comma to separate answers as needed.)
B. The domain is x x is any real number .
Transcript text: For the given functions f and g , complete parts (a)-(h). For parts (a)-(d), also find the domain.
\[
f(x)=x-8 ; g(x)=2 x^{2}
\]
$\qquad$
What is the domain of $\mathrm{f}-\mathrm{g}$ ? Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The domain is $\{x \mid$ $\square$ \}.
(Use integers or fractions for any numbers in the expression. Use a comma to separate answers as needed.)
B. The domain is $\{x \mid x$ is any real number $\}$.
Solution
Solution Steps
To find the domain of \( f - g \), we need to determine the set of all \( x \) values for which both \( f(x) \) and \( g(x) \) are defined. Since \( f(x) = x - 8 \) and \( g(x) = 2x^2 \) are both polynomials, they are defined for all real numbers. Therefore, the domain of \( f - g \) is all real numbers.
Solution Approach
The domain of \( f - g \) is all real numbers because both \( f(x) \) and \( g(x) \) are defined for all real numbers.
Step 1: Define the Functions
We have the functions defined as follows:
\[
f(x) = x - 8
\]
\[
g(x) = 2x^2
\]
Step 2: Determine the Domain of \( f \) and \( g \)
Both \( f(x) \) and \( g(x) \) are polynomial functions. Polynomial functions are defined for all real numbers. Therefore, the domain of each function is:
\[
\text{Domain of } f: \{ x \mid x \in \mathbb{R} \}
\]
\[
\text{Domain of } g: \{ x \mid x \in \mathbb{R} \}
\]
Step 3: Find the Domain of \( f - g \)
To find the domain of \( f - g \), we need to consider the intersection of the domains of \( f \) and \( g \). Since both functions are defined for all real numbers, the domain of \( f - g \) is also:
\[
\text{Domain of } (f - g): \{ x \mid x \in \mathbb{R} \}
\]
Final Answer
The domain of \( f - g \) is \(\boxed{\{ x \mid x \in \mathbb{R} \}}\).