1. The problem statement, all variables and given/known data This is part of a linear algebra problem. I've found the characteristic polynomial of a matrix however it's a degree 4 polynomial and I'm having trouble solving it 2. Relevant equations λ4+λ3-3λ2-λ+2 = 0 3. The attempt at a solution I replaced λ2 with a and did some manipulation, giving me 2 equations: a(a-3)+√a(a-1)=-2 and a(a-3)-√a(a-1)=-2 (not even sure if this is correct though). By inspection I can see that 1 is one of the solutions for a is 1 hence making λ 1 and -1 but I need a more rigorous and formal way of solving this.