2022TrialShort answer

Q11 (a) (i)

2 marks

Question

If $z=-\sqrt3+i$ and $w=1+i$ , find $\operatorname{Arg}(zw)$ in terms of $\pi$ .

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Solution

\arg z=\frac{5\pi}{6},\qquad \arg w=\frac{\pi}{4}

\operatorname{Arg}(zw)=\arg z+\arg w =\frac{5\pi}{6}+\frac{\pi}{4} =\frac{13\pi}{12}

\operatorname{Arg}(zw)= -\frac{11\pi}{12}

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Syllabus alignment

Complex Numbers

Geometric representation of a complex numberRepresent complex numbers in the complex plane and use modulus, argument and polar form with their identities.

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