
Michael M. answered 04/10/21
Math, Chem, Physics, Tutoring with Michael ("800" SAT math)
Polynomials wit zeros c1, c2, ... cn have factors (x - c1), (x - c2), ..., (x - cn)
Therefore a polynomial with zeros -5i, 1, 3, and 0 has factors (x+5i), (x -1), (x-3) and (x-0)
Because we need real coefficients, we have to include the conjugate of the -5i zero.
Therefore, 5i is another zero and another factor is (x - 5i)
So we can write a polynomial with these zeros as (x+5i)(x-5i)(x-1)(x-3)(x-0)
The x-0 can just be written as x.
So a polynomial with these factors would look like g(x) = x(x+5i)(x-5i)(x-1)(x-3)
We need a leading coefficient of 2. Right now, if we were to expand this, we would have a leading coefficient of 1, so we need to multiply this polynomial by 2.
g(x) = 2x(x+5i)(x-5i)(x-1)(x-3). This has a total of 5 complex zeros, so all the requirements are satisfied.