Выполните умножение: 1) (4a²-y)(y+4a²) 2) (0,3b³+х)(0,3b³-x) 3) (1,1c²+z²)(z²-1,1c²) 4) (21d²-k³)•(21d²+k³) 5) (5a³-4b²)(4b²+5a³) 6) (1,9c⁴+6d)(6d-1,9c⁴)

1) (4a² - y)(y + 4a²)  = 4a²y + 16a⁴ - y² - 4a²y = 16a⁴ - y²;

2) (0,3b³ + х)(0,3b³ - x) = 0,09b⁶ - 0,3b³x + 0,3b³x - x² = 0,09b⁶ - x²;

3) (1,1c² + z²)(z² - 1,1c²) = 1,1c²z² - 1,21c⁴ + z⁴ - 1,1c²z² = z⁴ - 1,21c⁴;

4) (21d² - k³)•(21d² + k³) = 441d⁴ + 21d²k³ - 21d²k³ - k⁶ = 441d⁴ - k⁶;

5) (5a³ - 4b²)(4b² + 5a³) = 20a³b² + 25a⁶ - 16b⁴ - 20a³b² = 25a⁶ - 16b⁴;

6) (1,9c⁴ + 6d)(6d - 1,9c⁴) = 11,4c⁴d - 3,61c⁸ + 36d² - 11,4c⁴d =

= 36d² - 3,61c⁸