To find \((f \cdot g \cdot h)(x)\), we first need to determine how these functions will combine through multiplication.
Given:
- \(f(x) = x - 2\)
- \(g(x) = 2x\)
- \(h(x) = \sqrt{x + 7}\)
The product \((f \cdot g \cdot h)(x)\) is calculated as follows:
\[ (f \cdot g \cdot h)(x) = f(x) \cdot g(x) \cdot h(x) = (x - 2) \cdot (2x) \cdot \sqrt{x + 7} \]
Now, breaking this down:
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First, multiply \(f(x)\) and \(g(x)\): \[ f(x) \cdot g(x) = (x - 2)(2x) = 2x^2 - 4x \]
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Then, multiply that result by \(h(x)\): \[ (2x^2 - 4x) \cdot \sqrt{x + 7} \]
So, we have: \[ (f \cdot g \cdot h)(x) = (2x^2 - 4x) \cdot \sqrt{x + 7} \]
This would not simplify further into a polynomial, since \(\sqrt{x + 7}\) is not a polynomial term.
Next, we need to determine the domain of \((f \cdot g \cdot h)(x)\):
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The function \(h(x) = \sqrt{x + 7}\) requires that: \[ x + 7 \geq 0 \implies x \geq -7 \]
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The functions \(f\) and \(g\) are polynomials and are defined for all real numbers.
Thus, the overall domain of \((f \cdot g \cdot h)(x)\) is limited by the square root function:
\[ \text{Domain} = [-7, \infty) \]
Consequently, combining these results:
\[ (f \cdot g \cdot h)(x) = (2x^2 - 4x) \sqrt{x + 7} \quad \text{and the domain is } x \geq -7. \]