Finding the angle between vectors a and m, knowing the magnitude of m and n

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SUMMARY

The discussion focuses on calculating the angle between vectors a and m, given the magnitudes of vectors m and n, and the angle between m and n, which is 60 degrees. The initial geometric approach suggested an angle of 30 degrees; however, the correct angle is 54.7 degrees. The formula provided for calculating the angle is based on the cosine of the angle, expressed as $$\cos \theta= \frac {\vec a . \vec m}{||\vec a|| ||\vec m||}$$, indicating the need for precise vector calculations to arrive at the correct answer.

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  • Knowledge of dot product calculations
  • Basic geometry concepts related to angles and magnitudes
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Summary: Finding angle between vectors a and m, knowing magnitude of m and n, also the angle between m and n with 60 degrees.

Screen Shot 2019-11-14 at 10.36.49 AM.png


Using geometry, it looks like the angle is 30 degrees but the answer is suppose to be 54.7 degrees. I'm not sure how to solve this.
 
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Hint:
$$\cos \theta= \frac {\vec a . \vec m}{||\vec a|| ||\vec m||}$$
 
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piesand said:
Summary: Finding angle between vectors a and m, knowing magnitude of m and n, also the angle between m and n with 60 degrees.

View attachment 252831

Using geometry, it looks like the angle is 30 degrees but the answer is suppose to be 54.7 degrees. I'm not sure how to solve this.
Sometimes the given answer is not true. Show, please, how did you get your result. It might be correct 😉
 
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Likes   Reactions: Chestermiller, Abhishek11235, Delta2 and 1 other person

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