Вправи: 555

555. Виконайте множення многочленів:

1) (m – n)(m + n) = m² – n²;

2) (х – 1)(х + 1) = х² – 1² = х² – 1;

3) (9 –y)(9 + у) = 9² – у² = 81 – у²;

4) (3b – 1)(3b + 1) – (3b)² – 1² = 9b² – 1;

5) (10m – 7)(10m + 7) = (10m)2 – 7² = 100m² – 49;

6) (4а – b)(b + 4a) = (4а – b)(4a + b) = (4a)² – b² = 16a² – b²;

7) (5b + 1)(1 – 5b) = (1 + 5b)(1 – 5b) = 1² – (5b)² = 1 – 25b²;

8) (3x – 5y)(3x + 5y) = (3x)² – (5y)² = 9x² – 25y²;

9) (13c– 10d)(13c + 10d) = (13c)² – (10d)² = 169c² – 100d²;

10) (8m + 11n)(11n – 8m) = (11n + 8m)(11n – 8m) = (11n)² – (8m)² = 121n² – 64m².