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

http://e.imagehost.org/0661/Screen_shot_2010-03-09_at_12_37_44_AM.png [Broken]

2. Relevant equations

Rotation Matrix:

cos(theta) -sin(theta)

sin(theta) cos(theta)

3. The attempt at a solution

I understand 2a:

cos(pi/4) -sin(pi/4)

sin(pi/4) cos(pi/4)

But I am not sure what 2b is looking for. Please help?

Thank you in advance for your help!

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# Homework Help: Rotation Matrices

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