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Complex numbers — Question 118

Original QCE Vault practice · 1 mark

Q118 · Practice questionTechnology-freeSimple familiar1 mark

QUESTION 118

If z=3cis⁡(π4)z=3\operatorname{cis}(\frac{\pi}{4}) and w=2cis⁡(π6)w=2\operatorname{cis}(\frac{\pi}{6}), then zwzw is
(A)
6cis⁡(5π12)6\operatorname{cis}(\frac{5\pi}{12})
(B)
(32)cis⁡(π12)(\frac{3}{2})\operatorname{cis}(\frac{\pi}{12})
(C)
5cis⁡(5π12)5\operatorname{cis}(\frac{5\pi}{12})
(D)
6cis⁡(π24)6\operatorname{cis}(\frac{\pi}{24})
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