Question
If $a=\cos \alpha+i \sin \alpha, b=\cos \beta+i \sin \beta c=\cos \gamma+i \sin \gamma$and $(a / b)+(b / c)+(c / a)=1$ then$\cos (\alpha-\beta)+\cos (\beta-\gamma)+\cos (\gamma-\alpha)=$(a) $(3 / 2)$(b) $-(3 / 2)$(c) 0(d) 1
Step 1
We can rewrite these as $a = e^{i\alpha}, b = e^{i\beta}, c = e^{i\gamma}$ using Euler's formula. Show more…
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