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## Homework Statement

Consider a thin homogeneous plate with a principal momenta of inertia. I1 along the principal axis x1, I

_{2}> I

_{1}along the principal axis x2. I

_{3}= I

_{1}+ I

_{2}.

Let the origins of the x

_{i}x'

_{i}systems coincide and be located at the center of mass O about an axis inclined at an angle a from the plane of the plate and perpendicular to the x

_{2}axis. If I

_{1}/ I

_{2}= cos(2a), show that at time t the angular velocity about the x

_{2}axis is

w

_{2}= omega*cos(a)*tanh(omega*t*sin(a))

## Homework Equations

## The Attempt at a Solution

I am having a hard time starting this problem.

So we know that angular momentum and energy should be conserved, but that doesn't appear to help me at all.

I'm thinking that Euler's equations should probably be used (force free)

(I

_{2}- I

_{3})w

_{2}w

_{3}- I

_{1}w'

_{1}= 0

(I

_{3}- I

_{1})w

_{3}w

_{1}- I

_{2}w'

_{2}= 0

(I

_{1}- I

_{2})w

_{1}w

_{2}- I

_{3}w'

_{3}= 0

But plugging in I

_{1}= I

_{2}*cos(2a) doesn't seem to yield anything..

Where does that tanh come from?

Anyone have any hints?