x² - 2x + 1 - 2(x - 1) = (x² - 2x + 1) - 2(x - 1) =(x - 1)² - 2(x - 1) =
= (x - 1)(x - 1 - 2) = (x - 1)(x - 3)
x² - 2x + 1 - 2(x - 1) = (x² - 2x + 1) - 2(x - 1) =(x - 1)² - 2(x - 1) =
= (x - 1)(x - 1 - 2) = (x - 1)(x - 3)