2023TrialMultiple choice

Q6

1 mark

Question

The polynomial $P(z)$ has real coefficients and $P(0)=-1$ . The imaginary number $\alpha$ and the real number $\beta$ satisfy $P(\alpha)=0$ , $P(\beta)=0$ and $P'(\beta)=0$ .

The degree of $P(z)$ is at least:

(A) $2$

(B) $3$

(D) $5$

Try the question before revealing the answer.

Syllabus alignment

ProofComplex Numbers

The Nature of ProofUse formal proof language, contradiction, counter-examples and rigorous arguments involving numbers and inequalities.
Solving equations with complex numbersUse De Moivre's theorem and solve equations and polynomial problems involving complex and conjugate roots.

Spot a problem? Send feedback