Hello

Please help me out with the question.

Given two unit vectors A,B and their sum (vector C) which is also a unit vector, find the angle between B and C?

Thanks in advance

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- Dec 2nd 2009, 09:18 PMMartin BilladoFinding angle between two unit vectors
Hello

Please help me out with the question.

Given two unit vectors A,B and their sum (vector C) which is also a unit vector, find the angle between B and C?

Thanks in advance - Dec 2nd 2009, 09:29 PMqmech
When working with vectors, you usually compute the angle by

$\displaystyle

cos \theta = \frac {\vec A \cdot \vec B}

{ A B }

$

where the denominators refer to the magnitude of the vectors.

In this case, since C = A + B is also a unit vector, are you working with an equilateral triangle? - Dec 2nd 2009, 10:44 PMMartin Billado
Thats what I thought and therefore wouldnt the answer be 60 degrees. But talking to my friend, she was arguing the answer is 120 degrees.

- Dec 3rd 2009, 02:43 AMmr fantastic