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Complex numbers 2 — Question 10

QCAA 2024, Paper 1 · 1 mark

Q10 · 2024 · Technology-freeSimple familiar1 mark

QUESTION 10

The polynomial P(z)=z3−2iz2+z−2iP(z)=z^3-2iz^2+z-2i can be expressed in factorised form as P(z)=(z−i)(z2+biz+2)P(z)=(z-i)(z^2+biz+2), where b∈Zb\in\mathbb Z. Determine the value of bb.
(A)
2
(B)
1
(C)
−1-1
(D)
−2-2
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