Solution
Given polynomila f(x) has real coefficients and of degree 3, and the the zeros of the ploynomial are -8 and 6 - i,
Analysing the given zeros,
we have one real zero , that is -8
we are also given a complex zero which is 6 - i
The remaining zero is the conjugate of the complex zero which is 6 + i
The answer is 6 + i
