find all the eigenvalues and eigenvectors for matrix B
b=
2 0 1 1
0 2 1 1
1 1 2 0
1 1 0 2
i understand how to do 3x3 matrices but cant get my head around 4x4
With all of those "2"s along the diagonal, always appear in " ". When I expand it, rather tham multiplying out powers of , I left them as powers and got . Letting , that equation becomes which has solutions x= 0 (a double root), x= 1, and x= -1. Since , is a double eigenvalue, and and are also eigenvalues.