Question

Which of the following is a polynomial with roots 3, 5i, and −5i?

Answer 1

$x_{1}=3 \\ \\ x_{2}=5i \\ \\ x_{2}=-5i \\ \\ f(x)=(x-x_{1})(x-x_{2})(x-x_{3})=(x-3)(x-5i)(x+5i)= \\ \\ =(x-3)(x^{2}+25)=x^{3}+25x-3x^{2}-75=x^{3}-3x^{2}+25x-75$

==================================

"Associate with people who are likely to improve you."