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

Find the magnitude of a and the smallest positive angle theta from the positive x-axis to the vector OP that corrosponds to a.

a= (3,-3)

2. Relevant equations

a_{1}= ||a|| * cos theta

a_{2}= ||a|| * sin theta

3. The attempt at a solution

||a|| = [tex]\sqrt{}[/tex](9+9) = 3[tex]\sqrt{}[/tex]2

a_{1}= 3[tex]\sqrt{}[/tex]2 * cos theta

=1/[tex]\sqrt{}[/tex]2 =acos = 45 degrees.

However doing the other side of the equation...

a_{2}= -1/[tex]\sqrt{}[/tex]2 = asin = -45 degrees = 315 degrees, which is the right answer. I thought they were supposed to be consistent...

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

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Trig: Angles of Vectors

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