Respuesta :
The correct answer is: if [tex] 1 + 13i [/tex] is a root of [tex] f(x) [/tex], then [tex] 1 - 13i [/tex] is also a root of [tex] f(x) [/tex].
In fact, every polynomial has real and/or complex solutions. If all solutions are real, we're good. But if not all of them are real, then the complex ones come in couple of conjugate solutions. Since [tex] 1 + 13i [/tex] and [tex] 1 - 13i [/tex] are conjugate complex numbers, if one of them is a solution, the other must be as well.