Questions: For the following function find (a) f(9), (b) f(-1/2), (c) f(a), (d) f(2/m), and (e) any values of x such that f(x)=1.
f(x) = (2x+6)/(x-9) if x ≠ 9
7 if x=9
(c) Find the value of f(a).
f(a) = (2a+6)/(a-9) if a ≠ 9
7 if a=9
(d) Find the value of f(2/m).
f(2/m) = (4+6m)/(2-9m) if m ≠ 2/9
7 if m=2/9
(e) Find the values of x such that f(x)=1.
x =
Transcript text: For the following function find (a) $f(9)$, (b) $f\left(-\frac{1}{2}\right)$, (c) $f(a)$, (d) $f\left(\frac{2}{m}\right)$, and (e) any values of $x$ such that $f(x)=1$.
\[
f(x)=\left\{\begin{array}{ll}
\frac{2 x+6}{x-9} & \text { if } x \neq 9 \\
7 & \text { if } x=9
\end{array}\right.
\]
(c) Find the value of $\mathrm{f}(\mathrm{a})$.
\[
f(a)=\left\{\begin{array}{ll}
\frac{2 a+6}{a-9} & \text { if } a \neq 9 \\
7 & \text { if } a=9
\end{array}\right.
\]
(d) Find the value of $f\left(\frac{2}{m}\right)$.
\[
f\left(\frac{2}{m}\right)=\left\{\begin{array}{ll}
\frac{4+6 m}{2-9 m} & \text { if } m \neq \frac{2}{9} \\
7 & \text { if } m=\frac{2}{9}
\end{array}\right.
\]
(e) Find the values of x such that $\mathrm{f}(\mathrm{x})=1$.
\[
\mathrm{x}=\square
\]
Solution
Solution Steps
Step 1: Evaluate \( f(9) \)
Since \( x = 9 \), we use the condition for \( f(x) \) when \( x = 9 \):
\[
f(9) = 7
\]
Step 2: Evaluate \( f\left(-\frac{1}{2}\right) \)
For \( x = -\frac{1}{2} \), which is not equal to 9, we use the other condition:
\[
f\left(-\frac{1}{2}\right) = \frac{2\left(-\frac{1}{2}\right) + 6}{-\frac{1}{2} - 9} = \frac{-1 + 6}{-\frac{1}{2} - 9} = \frac{5}{-\frac{19}{2}} = -\frac{10}{19}
\]
Step 3: Evaluate \( f(a) \)
For \( f(a) \), we consider the case when \( a \neq 9 \):
\[
f(a) = \frac{2a + 6}{a - 9}
\]
Step 4: Evaluate \( f\left(\frac{2}{m}\right) \)
For \( m \neq \frac{2}{9} \), we have:
\[
f\left(\frac{2}{m}\right) = \frac{4 + 6m}{2 - 9m}
\]
Step 5: Solve for \( x \) such that \( f(x) = 1 \)
To find \( x \) such that \( f(x) = 1 \), we set up the equation:
\[
\frac{2x + 6}{x - 9} = 1
\]
Cross-multiplying gives:
\[
2x + 6 = x - 9
\]
Rearranging leads to:
\[
2x - x = -9 - 6 \implies x = -15
\]