Eric Nicholas K's answer to lim's Junior College 2 H3 Maths Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
Part i, I finally recalled my complex numbers slightly
J
J
4 years ago
Shorter alternative for i) :

(c - a)e^⅓πi

= ce^⅓πi - ae^⅓πi

= re^(θ + 4/3π+⅓π)i - re^(θ + ⅓π)i

= re^(θ+5/3π)i - (- re^(θ + ⅓π + π)i )

= -re^(θ +5/3π - π)i + re^(θ + 4/3π)i

= -re^(θ + ⅔π)i + c

= c - b