Answer:
-2 - the square root of 3i is a known root
Explanation:
we know that
The conjugate root theorem states that if the complex number a + bi is a root of a polynomial P(x) in one variable with real coefficients, then the complex conjugate a - bi is also a root of that polynomial
we have that
The root of a function is
![-2+√(3)i](https://img.qammunity.org/2021/formulas/mathematics/middle-school/3i2cis9tg2v261w8i98sywx4munqg05ue5.png)
so
Applying the conjugate root theorem
---> is also a root of the function
therefore
-2 - the square root of 3i is a known root