4. Раскройте скобки. 1) (b - c)(b + c) 2) (k + m)(k – m) 3) (c – 1)(c + 1) 4) (2 + k)(2 – k) 5) (6 – a)(a + 6) 6) (x + 144a)(x – 144a) 7) (5m – 3k)(3k + 5m) 8) (12v – 11u)(11u + 12v) 9) (9p + n²)(n² – 9p) 10) (15a3 – 2b²)(15a³ + 2b²) 11) (6h² - 17m²)(6h² + 17m²) 12) (11x² - 7z³)(11x² + 7z³) 13) (8u6 - 5b²)(8u6 + 5b²) 14) (13a7 – 18v3)(13a7 + 18v3) 15) (20p10 - 19k3)(20p10 + 19k3)

1) \[(b - c)(b + c) = b^2 - c^2\] 2) \[(k + m)(k - m) = k^2 - m^2\] 3) \[(c - 1)(c + 1) = c^2 - 1\] 4) \[(2 + k)(2 - k) = 4 - k^2\] 5) \[(6 - a)(a + 6) = (6-a)(6+a) = 36 - a^2\] 6) \[(x + 144a)(x - 144a) = x^2 - (144a)^2 = x^2 - 20736a^2\] 7) \[(5m - 3k)(3k + 5m) = (5m - 3k)(5m + 3k) = 25m^2 - 9k^2\] 8) \[(12v - 11u)(11u + 12v) = (12v - 11u)(12v + 11u) = 144v^2 - 121u^2\] 9) \[(9p + n^2)(n^2 - 9p) = (n^2 + 9p)(n^2 - 9p) = n^4 - 81p^2\] 10) \[(15a^3 - 2b^2)(15a^3 + 2b^2) = 225a^6 - 4b^4\] 11) \[(6h^2 - 17m^4)(6h^2 + 17m^4) = 36h^4 - 289m^8\] 12) \[(11x^2 - 7z^3)(11x^2 + 7z^3) = 121x^4 - 49z^6\] 13) \[(8u^6 - 5b^2)(8u^6 + 5b^2) = 64u^{12} - 25b^4\] 14) \[(13a^7 - 18v^3)(13a^7 + 18v^3) = 169a^{14} - 324v^6\] 15) \[(20p^{10} - 19k^3)(20p^{10} + 19k^3) = 400p^{20} - 361k^6\]