144. Разложите на множители: 1) 7x² - 28; 2) 3a³ - 108a; 3) 3x⁴ - 3x²y²; 4) 4m²n² - 64m²p²;

1) $$7x^2 - 28 = 7(x^2 - 4) = 7(x - 2)(x + 2)$$ 2) $$3a^3 - 108a = 3a(a^2 - 36) = 3a(a - 6)(a + 6)$$ 3) $$3x^4 - 3x^2y^2 = 3x^2(x^2 - y^2) = 3x^2(x - y)(x + y)$$ 4) $$4m^2n^2 - 64m^2p^2 = 4m^2(n^2 - 16p^2) = 4m^2(n - 4p)(n + 4p)$$