To find \((f - g - h)(x)\), we need to calculate \(f(x) - g(x) - h(x)\).
Given the functions:
- \( f(x) = -5x^2 + 4 \)
- \( g(x) = -4x^2 - 7x + 9 \)
- \( h(x) = 2x^2 + x - 2 \)
Let's perform the calculation step-by-step:
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Calculate \(f(x) - g(x)\): \[ f(x) - g(x) = (-5x^2 + 4) - (-4x^2 - 7x + 9) \] This simplifies to: \[ -5x^2 + 4 + 4x^2 + 7x - 9 = (-5x^2 + 4x^2) + 7x + (4 - 9) = -x^2 + 7x - 5 \]
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Now, subtract \(h(x)\): \[ (f(x) - g(x)) - h(x) = (-x^2 + 7x - 5) - (2x^2 + x - 2) \] This simplifies to: \[ -x^2 + 7x - 5 - 2x^2 - x + 2 = (-x^2 - 2x^2) + (7x - x) + (-5 + 2) = -3x^2 + 6x - 3 \]
So, we find that: \[ (f - g - h)(x) = -3x^2 + 6x - 3 \]
- Now, let's determine the domain of \((f - g - h)(x)\): Since \(f(x)\), \(g(x)\), and \(h(x)\) are all polynomials, their domain is all real numbers. Consequently, the domain of \((f - g - h)(x)\) is also all real numbers.
Thus, the correct response is: \[ (f - g - h)(x) = -3x^2 + 6x - 3 \quad \text{and the domain of } (f - g - h)(x) \text{ is } (-\infty, \infty). \]
So the correct option is: \[ (f - g - h)(x) = -3x^2 + 6x - 3 \text{ and the domain of } (f - g - h)(x) \text{ is } (-\infty, \infty). \]