## Algebra: A Combined Approach (4th Edition)

$x^4-3x^2+1$
Shaded area = Larger square - smaller square Larger square $= (x^2-1) \times (x^2-1)$ $= x^4-2x^2+1$ Smaller square $= x \times x$ $=x^2$ $(x^4-2x^2+1)-(x^2)$ $=x^4-3x^2+1$