To find \((f \cdot g \cdot h)(x)\), we need to multiply the three functions together:
- \(f(x) = x - 2\)
- \(g(x) = 2x\)
- \(h(x) = \sqrt{x + 7}\)
The composition of these functions is given by:
\[ (f \cdot g \cdot h)(x) = f(x) \cdot g(x) \cdot h(x) \]
Calculating step by step:
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Calculate \(f(x) \cdot g(x)\):
\[ f(x) \cdot g(x) = (x - 2)(2x) = 2x^2 - 4x \]
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Now multiply this result by \(h(x)\):
\[ (f \cdot g)(x) \cdot h(x) = (2x^2 - 4x) \cdot \sqrt{x + 7} \]
So:
\[ (f \cdot g \cdot h)(x) = (2x^2 - 4x) \sqrt{x + 7} \]
Next, we determine the domain of \((f \cdot g \cdot h)(x)\). The domain is constrained by the square root function \(h(x) = \sqrt{x + 7}\), which requires:
\[ x + 7 \geq 0 \implies x \geq -7 \]
Thus, the domain of \((f \cdot g \cdot h)(x)\) is:
\[ [x \geq -7 \text{ or } [-7, \infty) \]
In conclusion, we have:
\[ (f \cdot g \cdot h)(x) = (2x^2 - 4x) \sqrt{x + 7} \] and the domain is:
\[ x \geq -7 \] (or written in interval notation, \([-7, \infty)\)).