(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] Angle between vectors:

1. The problem statement, all variables and given/known data

What is the angle between A and B ? Answer in units of degree.

2. Relevant equations

From the previous problem:

A = 1.02 units long in positive y direction [0i + 1.02j]

B = [-6.18i + 3.64j]

3. The attempt at a solution

I got the question from the previous part right, finding scalar product of the 2 vectors. So I know the vectors are set up correctly.

I am under the impression that [tex]\theta[/tex] = [tex]\theta[/tex]b - [tex]\theta[/tex]a

Arctan of (-1.02/0 ) gives an error ( obviously ) so i just did arctan of (-1.02) = 45.567 degrees

Arctan of (3.64 / -6.18 ) gives a degree of -30.497

When doing the answer, I got [tex]\theta[/tex] = 76.064. I tried this as both a negative and a positive and I was wrong.

What am I missing here? Is one angle supposed to change sign? Is my order wrong? Maybe my arctan of (1.02) is wrong?

Thanks

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# Homework Help: Angle between vectors:

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