Question 345438
(X-1)^(2)-4

The binomial can be factored using the difference of squares formula, because both terms are perfect squares.  The difference of squares formula is X^(2)-b^(2)=(X-b)(X+b).
((X-1)-2)((X-1)+2)

Remove the parentheses around the expression X-1.
(X-1-2)((X-1)+2)

Subtract 2 from -1 to get -3.
(X-3)((X-1)+2)

Remove the parentheses around the expression X-1.
(X-3)(X-1+2)

Add 2 to -1 to get 1.
(X-3)(X+1)