Answer:

Step-by-step explanation:
<u>Complex Conjugate Theorem</u>
For a polynomial p(x) with real coefficients, the complex zeros occur in <u>conjugate pairs</u>. So if (a + bi) is a zero, then its conjugate (a - bi) is also a zero.
<u>Given zeros</u>:
-1, 3, and (2 + 4i)
As one of the given zeros is a <u>complex number</u>, (2 - 4i) is also a zero.
Write each zero as part of a factor and multiply them together, adding a <u>leading coefficient</u>
:

Remember that
, therefore:

To find the value of the leading coefficient (a), use the given
:

Therefore, the polynomial in factored form is:

Finally, expand the brackets:

Learn more about complex numbers here:
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