[tex]f(x) + g(x) = 3x + 2 + x + 6 = 4x + 8[/tex]. This function is defined for all real numbers.
[tex]f(x) - g(x) = (3x + 2) - (x + 6) = 2x - 4[/tex]. This function is also defined for all real numbers.
[tex]f(x) \cdot g(x) = (3x + 2) \cdot (x + 6) = 3x^2 + 2x + 18x + 12 = 3x^2 + 20x + 12.[/tex] As before, this function is defined for all real numbers [tex]x[/tex].
[tex]\frac{f(x)}{g(x)} = \frac{3x+2}{x+6}[/tex]. Fractions are undefined when their denominators are zero, so if [tex]x + 6 = 0[/tex], this function is undefined. Thus, the domain is all real numbers except [tex]x = -6[/tex].