To find \((f \circ g)(x)\), we first need to substitute \(g(x)\) into \(f(x)\).
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Finding \((f \circ g)(x)\):
The function \(g(x) = x - 4,000\). Now substitute \(g(x)\) into \(f(x)\):
\[ f(g(x)) = f(x - 4,000) = 0.04(x - 4,000) = 0.04x - 0.04 \cdot 4,000 \] \[ f(g(x)) = 0.04x - 160 \]
So, we have \((f \circ g)(x) = 0.04x - 160\).
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Meaning:
This means that \((f \circ g)(x)\) represents the amount Sally earns in commission based on her total sales, where \(x\) is the total sales amount in dollars. The term \(-160\) represents the threshold amount that needs to be surpassed (the $4,000 in sales) before Sally starts earning commission from her sales.
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Domain:
Since \(g(x)\) gives the amount of sales on which Sally earns commission, it requires \(g(x) \geq 0\).
Therefore, we require:
\[ x - 4,000 \geq 0 \Rightarrow x \geq 4,000 \]
Thus, the domain of \((f \circ g)(x)\) is \(x \geq 4,000\).
Correct response:
\((f \circ g)(x) = 0.04x - 160\) represents the amount Sally earns in commission. The domain is \(x \geq 4,000\).