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

So here is the question:

Matrix A corresponds to the linear transformation T obtained by first rotating a vector in R3 through angle ∏/3 about the z axis and then through angle ∏/4 about the x-axis. Find the parametric equation for the axis of rotation.

2. Relevant equations

3. The attempt at a solution

Finding matrix A: First I write down the two standard rotations with the first one on the right and multiply them:

This gives me matrix A. I then take the result and subtract the 3x3 identity matrix (so Mat(A) - I3). I augment this by the 3x1 zero vector and rref. So the following is what I am rref-ing. (so I am solving this system (A-I)[w]=0, and the axis parallel to [w] is the axis of rotation)

But when I rref this, I get the following:

W3=t where t is in the reals

W2=-0.4142t

W1=0.7174t

This doesn't seem right to me.. so the parametric form of the axis of rotation is this:

x=0.7174t

y=-0.4142t

z=t

Thanks so much in advance!

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# Homework Help: Am I doing this right? Doesn't feel right. (find axis of rotation)

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