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Further complex numbers — Question 258

Original QCE Vault practice · 4 marks

Q258 · Practice questionTechnology-freeSimple familiar4 marks

QUESTION 258 (4 marks)

Let z=a+biz=a+bi and w=c+diw=c+di, where a,b,c,d∈Ra,b,c,d\in\mathbb R.
a)
Prove ∣zw∣=∣z∣∣w∣|zw|=|z||w| using Cartesian form. Your proof must also cover a zero value of either number.
[4 marks]
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