To find \((f \cdot g \cdot h)(x)\), we will first express it in terms of the given functions and then determine the domain.
Given Functions:
- \( f(x) = x - 2 \)
- \( g(x) = 2x \)
- \( h(x) = \sqrt{x + 7} \)
Calculating \((f \cdot g \cdot h)(x)\): \[ (f \cdot g \cdot h)(x) = f(x) \cdot g(x) \cdot h(x) \]
Substituting the functions: \[ = (x - 2) \cdot (2x) \cdot \sqrt{x + 7} \]
Now, we simplify it:
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First, calculate \(f(x) \cdot g(x)\): \[ f(x) \cdot g(x) = (x - 2)(2x) = 2x^2 - 4x \]
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Now multiply by \(h(x)\): \[ (2x^2 - 4x) \cdot \sqrt{x + 7} = (2x^2 - 4x) \sqrt{x + 7} \]
Thus, we have: \[ (f \cdot g \cdot h)(x) = (2x^2 - 4x) \sqrt{x + 7} \]
Finding the Domain: The domain of \((f \cdot g \cdot h)(x)\) is determined by the domain restrictions of the functions involved:
- For \(f(x) = x - 2\), there are no restrictions: it is defined for all \(x \in (-\infty, \infty)\).
- For \(g(x) = 2x\), there are also no restrictions: it is defined for all \(x \in (-\infty, \infty)\).
- For \(h(x) = \sqrt{x + 7}\), we require: \[ x + 7 \geq 0 \implies x \geq -7 \]
Therefore, the domain of \((f \cdot g \cdot h)(x)\) is: \[ x \geq -7 \text{ or } [-7, \infty) \]
Final Answer: \((f \cdot g \cdot h)(x) = (2x^2 - 4x) \sqrt{x + 7}\)
And the domain of \((f \cdot g \cdot h)(x)\) is \(x \geq -7\) or \( [-7, \infty) \).