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Complex numbers 2 — Question 1

QCAA 2022, Paper 1 · 1 mark

Q1 · 2022 · Technology-freeSimple familiar1 mark

QUESTION 1

Let z=a+3iz=a+3i and w=−3+biw=-3+bi, where a,b∈Ra,b\in\mathbb R.
If z=wz=w, then
(A)
a=−3,  b=−3a=-3,\;b=-3
(B)
a=−3,  b=3a=-3,\;b=3
(C)
a=3,  b=−3a=3,\;b=-3
(D)
a=3,  b=3a=3,\;b=3
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