Respuesta :

Answer:

[tex]f(x)g(x) = (3 - i)(4i) \\ = 12i - 4 {i}^{2} \\ = \boxed{12i + 4 }\\ remember \:the \: value \: of \: {i}\: is \: \sqrt{ - 1} \\ and \: {i}^{2} \: is - 1 \\ d. (4 + 12i)\: is \: the \: right \: answer.[/tex]