how do i factor the polynomial x^4-2x^2 1-a^2 by grouping?
Assuming that this is the equation that you were meaning, here is the factoring completed. You could also factor out a -1 from the last two terms and rewrite as follows ( -(a^2-1)). Willard
Treat "x2" as a unit by itself (that is, let y = x2, and rewrite your expression in terms of y. Now you can factor the quadratic. Finally, replace y with "x2" to present your result.
there's a small problem with your equation inbetween the 2x^2 and 1-a^2 terms which doesn't lead me to any decisions....