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# Polar and cartesian coordinates watch

1. Attachment 694632694634
Attachment 694632694634694700

Where did I mess up?
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2. (Original post by ckfeister)
Where did I mess up?
Information in the question is presented in polar form, in particular the coordinates of P and Q.

To find the midpoint of P and Q, you cannot just add the two sets of coordinates and divide by 2, when they are in polar form.

Easiest way would be to express P,Q in cartesian initially, then you can add the two and divide by 2 to find the midpoint - in Cartesian.

And finally convert to polar
3. (Original post by ghostwalker)
Information in the question is presented in polar form, in particular the coordinates of P and Q.

To find the midpoint of P and Q, you cannot just add the two sets of coordinates and divide by 2, when they are in polar form.

Easiest way would be to express P,Q in cartesian initially, then you can add the two and divide by 2 to find the midpoint - in Cartesian.

And finally convert to polar
Thanks and how do I do c) ?
4. (Original post by ckfeister)
Thanks and how do I do c) ?
Since the straight line OM goes through the pole, what's the angle that any point on it makes with the initial line? Hence the desired point on the curve will have

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