(1,1x² - 6y)² - (1,1x² - 6y)(1,1x² + 6y) =
= (1,1x² - 6y)(1,1x² - 6y) - (1,21x⁴ - 36y²) =
= 1,21x⁴ - 6,6x²y - 6,6x²y + 36y² - 1,21x⁴ + 36y² =
= -13,2x²y + 72y²
(2,3a - 7b³)(2,3a + 7b³) - (2,3a + 7b³)² = (2,3a - 7b³)(2,3a + 7b³) -
- (2,3a + 7b³)(2,3a + 7b³) =
= 5,29a² - 49b⁶ - (5,29a² + 16,1b³a + 16,1b³a + 49b⁶) =
= 5,29a² - 49b⁶ - (5,29a² + 32,2b³a + 49b⁶) =
= 5,29a² - 49b⁶ - 5,29a² - 32,2b³a - 49b⁶ =
= -98b⁶ - 32,2b³a
(3,1n³ - 5m)² + (5m - 3,1n³)(5m - 3,1n³) = (3,1n³ - 5m)(3,1n³ - 5m) +
+ (5m - 3,1n³)(5m - 3,1n³) =
= 9,61n⁶ - 15,5n³m - 15,5n³m + 25m² +
+ 25m²- 15,5n³m - 15,5n³m + 9,61n⁶=
= 19,22n⁶ - 62n³m + 50m²
