Undergrad On the Coriolis Forcing vector and its Matrix

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The discussion revolves around the differential equation governing Q(t) and its implications for trajectories given initial conditions. It highlights that if Q(t0) z(t0) = z(t0) holds for all z(t0) ∈ ℝn, then Q(t0) must equal the identity matrix I. The inquiry raises questions about the commutation of R with Q(t), given that R's basis vectors are arbitrary. It concludes that the matrix expression for Q(t) is dependent on the chosen orthonormal basis, suggesting that the answer pertains to the trajectory of a single point rather than a general case. The conversation emphasizes the intricacies of matrix representations in varying bases.
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The context for the question is in the attachments (pg1.png, pg2.png, pg3.png), so there is some reading involved. Although, it is a short and simple read if anything. The inquiry is in (inquiry.png).
My understanding of the situation is that Q(t) abides by the differential equation
Q'(t)Q(t)T + Q(t)Q'(t)T = 0 .
So by something akin to Picard's existence theorem on differential equations, we can resolve exact trajectories for Q(t) given initial conditions. The peculiar thing is that
Q(t0) z(t0) = z(t0)
can likely be assumed to be true for all z(t0) ∈ ℝn, in which case
Q(t0) = I
should also be true.
Now if I let R = ( i(t0) , j(t0) , k(t0) ), then
RTR = RRT = I ,
and the question insists that
RTQ(t)R = Q ⇒ Q(t)R = RQ(t).
Although, our choice of the initial condition basis vectors for R is arbitrary, so how can we expect that R necessarily commutes with Q(t)? Unless of course, the question is asking for the matrix expression of Q(t) in the { i(t0) , j(t0) , k(t0) } basis. I am just wondering if I am to expect the matrix expression of Q(t) to remain invariant given any orthonormal basis of the same orientation?
(Also, how do I insert latex?)
 

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Well, by the looks of it, the matrix expression for Q(t) would change depending on the basis { i(t0) , j(t0) , k(t0) } used. So I suppose the answer is simply in the context of the trajectory of one point.
 

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