Questions: Refer to the functions r, p, and q. Find the function (r/q)(x) and write the domain in interval notation.
r(x) = 4x
p(x) = x^2 + 2x
q(x) = sqrt(8-x)
Part: 0 / 2
Part 1 of 2
(r/q)(x) =
Transcript text: Refer to the functions $r, p$, and $q$. Find the function $\left(\frac{r}{q}\right)(x)$ and write the domain in interval notation.
\[
r(x)=4 x \quad p(x)=x^{2}+2 x \quad q(x)=\sqrt{8-x}
\]
Part: $0 / 2$
Part 1 of 2
\[
\left(\frac{r}{q}\right)(x)=
\]
$\square$
Solution
Solution Steps
Step 1: Define the Function \(\left(\frac{r}{q}\right)(x)\)
To find the function \(\left(\frac{r}{q}\right)(x)\), we need to divide the function \(r(x)\) by the function \(q(x)\).
Given:
\[ r(x) = 4x \]
\[ q(x) = \sqrt{8-x} \]
The function \(\left(\frac{r}{q}\right)(x)\) is defined as:
\[
\left(\frac{r}{q}\right)(x) = \frac{r(x)}{q(x)} = \frac{4x}{\sqrt{8-x}}
\]
Step 2: Determine the Domain of \(\left(\frac{r}{q}\right)(x)\)
The domain of \(\left(\frac{r}{q}\right)(x)\) is determined by the restrictions on \(q(x)\), since division by zero is undefined and the square root function requires non-negative arguments.
Square Root Restriction: The expression under the square root, \(8-x\), must be non-negative:
\[
8-x \geq 0 \implies x \leq 8
\]
Denominator Restriction: The denominator \(\sqrt{8-x}\) cannot be zero:
\[
\sqrt{8-x} \neq 0 \implies 8-x \neq 0 \implies x \neq 8
\]
Combining these conditions, the domain of \(\left(\frac{r}{q}\right)(x)\) is:
\[
x \leq 8 \quad \text{and} \quad x \neq 8
\]
Thus, the domain in interval notation is:
\[
(-\infty, 8)
\]
Final Answer
The function \(\left(\frac{r}{q}\right)(x)\) is:
\[
\left(\frac{r}{q}\right)(x) = \frac{4x}{\sqrt{8-x}}
\]
The domain of \(\left(\frac{r}{q}\right)(x)\) is:
\[
\boxed{(-\infty, 8)}
\]