(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A man travels 12 kilometres northeast, 20 kilometres 30° west of north and finally

18 kilometres 60° south of west. Determine his position with respect to his starting point.

2. Relevant equations

Using complex numbers

z = a + ib

|z|(cosx°+sinx°)

3. The attempt at a solution

Well I thought about plotting these on a argand diagram and concatenating them with one another:

a = 12cos45 + i12sin45

b = 20cos30 + i20sin30

c = -60cos60 + -i60sin60 (im sure you could turn these into 30s)

I guessimated that the resulting vector should be somewhere in the top left quadrant?

Adding up the components and the cosine components and dividing one by the other, then taking the inverse tangent does no yeild the correct result.

Am I even going in the right direction?

Thanks

Thomas

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# Homework Help: Using complex numbers to represent distances

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