Question

write plynomial in standard form 3,-13, and 5+4i

Answer 1

Complex numbers cannot exist independently so, the roots of the equation are
3,-13,5+4i and its conjugate 5-4i
so we have four factors a,b,c,d, then it becomes biquadratic equation
and the equation is
\[(x-a)(x-b)(x-c)(x-d)=0\]