# what are similarity invariants for companion matrix?

#### chickenwin

##### New member
[SOLVED] what are similarity invariants for companion matrix?

here is how companion matrix is defined Companion matrix - Wikipedia, the free encyclopedia

similarity invariant i think is basically the unique roots of characteristic polynomial. like (x-p1) (x-p2) (x-p3) etc.

the first thing that jumps to my mind is trying to do A-rI and trying to write out character poly as (x-p1) (x-p2) etc but that seems like a nightmare.

edit: NVM DONE.

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