Question 728838
Wanting a degree three polynomial function and having the three roots means you can just write the factors which make the minimum function.  You're already given that coefficient on x is 1.


{{{f(x)=(x+1)(x+5i)(x-5i)}}}
If you want, you can multiply the two complex factors to get a quadratic factor:
{{{x^2-(5i)^2=x^2+25}}}, so to have {{{f(x)=(x+1)(x^2+25)}}}.