1. The problem statement, all variables and given/known data Find the roots of x^4 - 6x^2 - 2 2. Relevant equations 3. The attempt at a solution So my first observation is that this polynomial is irreducible by Eisenstein criterion with p=2. If I substitute y=x^2 then this polynomial becomes a quadratic, and I can apply the quadratic equation to get two solutions for y. Then could I take the +/- of the square root of these solutions to get the roots in terms of x? If so, is there a simpler way to find these roots? Thanks PF!