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Real coefficients and a known complex root

Consider the equation 2z3+pz2+qz−65=02z^3+pz^2+qz-65=0.

(i) If pp and qq are real numbers, what are the possibilities for real and complex roots for this equation?

It is given that z=3+2iz=3+2i is a root of the equation 2z3+pz2+qz−65=02z^3+pz^2+qz-65=0, where pp and qq are real numbers.

(ii) Find the values of pp and qq.

[2013/NJC/I/11(a)(modified)]

CJC · Discussion · Question 5

Use the real-coefficient condition before invoking conjugate pairs.

Read the worked solution