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

3. The attempt at a solution

I understand how to get the derivatives for velocity and acceleration but when the book plugs in the numbers I disagree.

velocity at pi

2 sin pi/2 = 0

2 cos pi/2 = -1j

therefore, 0 + - 1j = -1j (the books says -2i)

velocity at (3pi)/2

2 sin 3pi/2 = 0

2 cos 3pi/2 = 1i

therefore, 0 + 1i = 1i (the book says -√2i - √2j)

acc at pi

-cos pi/2 = 1/2i

-sin pi/2 = 0

therefore, 1/2i + 0 = 1/2i (the book says -1j)

acc at (3pi/2)

-cos 3pi/2 = 0

-sin 3pi/2 = 1/2j

therefore, 1/2j (the book says -√2/2i - √2/2j)

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# Homework Help: Vector motion in a circle

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