(b-1)²*(1/b²-2b+1 + 1/b²-1)+2/b+1

1) 1/(b² - 2 * b + 1) + 1/(b² - 1) = 1/(b - 1)² + 1/((b - 1) * (b + 1));

2) (b - 1)² * (1/(b - 1)² + 1/((b - 1) * (b + 1))) = (b - 1)²/(b - 1)² + (b - 1)²/((b - 1) * (b + 1)) = 1 + ((b - 1) * (b - 1))/((b - 1) * (b + 1)) = 1 + (b - 1)/(b + 1);

3) 1 + (b - 1)/(b + 1) + 2/(b + 1) = 1 + (b - 1 + 2)/(b + 1) = 1 + (b + 1)/(b + 1) = 1 + 1 = 2.

Ответ: 2.