MathCastle
Linear AlgebraHardEigenvalues

Eigenvalues · Hard problem

A rigid body spins so that the velocity of the point at position r\mathbf r is v=Ωr\mathbf v = \Omega\mathbf r, where Ω=(0−3230−1−210)\Omega = \begin{pmatrix}0 & -3 & 2\\3 & 0 & -1\\-2 & 1 & 0\end{pmatrix} is skew-symmetric (ΩT=−Ω\Omega^T = -\Omega). Points on the instantaneous rotation axis have zero velocity, so the axis direction is an eigenvector of Ω\Omega for eigenvalue 00. Writing that eigenvector as (1,b,c)(1, b, c), find b+cb + c.