To find \((f \cdot g)(x)\), we need to multiply \(f(x)\) and \(g(x)\).
Given: \[ f(x) = 3x + 1 \] \[ g(x) = |x + 3| - 5 \]
The product \((f \cdot g)(x)\) can be calculated as follows: \[ (f \cdot g)(x) = f(x) \cdot g(x) = (3x + 1) \cdot (|x + 3| - 5) \]
Now let’s expand this: \[ (f \cdot g)(x) = (3x + 1)(|x + 3| - 5) = (3x + 1)|x + 3| - 5(3x + 1) \] \[ = (3x + 1)|x + 3| - (15x + 5) = (3x + 1)|x + 3| - 15x - 5 \]
This means: \[ (f \cdot g)(x) = (3x + 1)|x + 3| - 15x - 5 \]
Now simplify: \[ = 3x|x + 3| + |x + 3| - 15x - 5 \]
The domain of \((f \cdot g)(x)\) is determined by the domains of \(f(x)\) and \(g(x)\). Both functions \(f(x)\) and \(g(x)\) are defined for all real numbers.
The domain of \((f \cdot g)(x)\) is therefore: \[ (-\infty, \infty) \]
Conclusion:
\((f \cdot g)(x) = (3x + 1)|x + 3| - 15x - 5\) and the domain of \((f \cdot g)(x)\) is \((-∞, ∞)\).
However, it looks like none of the provided response options precisely reflect this outcome. The closest conclusion would be that the domain is indeed \((-∞, ∞)\).
Please ensure to check the representation in the options you provided to see if similar structures are mentioned so you can select the most appropriate response based on my detailed explanation.