To determine \((f + g + h)(x)\), we need to combine the functions \(f(x)\), \(g(x)\), and \(h(x)\):
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Functions given:
- \(f(x) = -x^4 + 7x^2 + 6\)
- \(g(x) = |x - 7| + 1\)
- \(h(x) = \sqrt{x + 3} - 8\)
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Combine the functions: \[ (f + g + h)(x) = f(x) + g(x) + h(x) \] \[ = (-x^4 + 7x^2 + 6) + (|x - 7| + 1) + (\sqrt{x + 3} - 8) \] \[ = -x^4 + 7x^2 + 6 + |x - 7| + 1 + \sqrt{x + 3} - 8 \] \[ = -x^4 + 7x^2 + |x - 7| + \sqrt{x + 3} - 1 \]
Thus, \[ (f + g + h)(x) = -x^4 + 7x^2 + |x - 7| + \sqrt{x + 3} - 1 \]
- Determine the domain:
- The domain of \(f(x)\) (a polynomial) is all real numbers, \((-∞, ∞)\).
- The domain of \(g(x) = |x - 7| + 1\) is also all real numbers, \((-∞, ∞)\).
- The function \(h(x) = \sqrt{x + 3} - 8\) requires that the argument of the square root is non-negative: \[ x + 3 \geq 0 \quad \Rightarrow \quad x \geq -3 \] Therefore, the domain of \(h(x)\) is \([-3, ∞)\).
Since \(h(x)\) restricts the overall domain, the domain of \((f + g + h)(x)\) is: \[ [-3, ∞) \]
Final Answer
\[ (f + g + h)(x) = -x^4 + 7x^2 + |x - 7| + \sqrt{x + 3} - 1 \] The domain of \((f + g + h)(x)\) is \(x \geq -3\) (or in interval notation, \([-3, ∞)\)).