x^2 - 2x +1 - 100y^4 = ?
Answer Choices:
a) (100y^2 + x - 1)(-100y^2 + x - 1)
b) (x^2 - 3x)(1 - 100y^4)
c) (3x + 1)(x^2 - 100y^4)
d) x(x-3) -1(1 - 100y^4)

Oh phooey! Greenstamps did it for you.  I was going to do another one
exactly like it, only with different numbers so you couldn't get credit for
what somebody else did.  Anyway here's the one that was exactly like it that
I was going to give you.

x2 - 4x + 4 - 25y4

Factor the first three terms:

(x - 2)(x - 2) - 25y4

Since the first factorization has both factors equal, write

it as one of them squared:

(x - 2)2 - 25y4

That factors as the difference of two squares.

[(x - 2) - 5y][(x - 2) + 5y]

Remove the parentheses inside the brackets:

[x - 2 - 5y][x - 2 + 5y]

Rearrange the terms so that the constant terms come last,
and the letter terms are first in alphabetical order.  Also
change the brackets to parentheses

(x - 5y - 2)(x + 5y - 2)

Edwin