FLMPotD

[ultrawaffle]

Show that x^4-16x^2+4 is reducible mod p for every prime p.

(Stolen from a comment by secret_panda on a post on somthng2remembr's facebook. Yay stalking!)

(PS: Actually, my argument should work for anything of the form x^4+bx^2+c^2 for b and c integers and p odd.)

Comments

[secret_panda]

(I think it has to be c^4+2bx^2+c^2? Using the proof with Galois Theory that I'm not allowed to use. Rawr.)