Let $f(x) = 4x+1$ and $g(x)= 3x.$ Find $f \circ g$ and $g \circ f$, and their respective domains. Simplify your answers.

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1. $(f \circ g)(x) =$

2. What is the domain of $f \circ g$ ?
Answer (in interval notation):

3. $(g \circ f)(x) =$

4. What is the domain of $g \circ f$ ?
Answer (in interval notation):

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