(a + 2b)^2 - (a - 2b)^2 =(a + 2b)(a + 2b) - (a - 2b)(a - 2b) =a^2 + 4ab + 4b^2 - (a^2 - 4ab + 4b^2) =a^2 + 4ab + 4b^2 - a^2 + 4ab - 4b^2 =8ab + 8b^2
Ответ: 8ab + 8b^2
(a + 2b)^2 - (a - 2b)^2 =
(a + 2b)(a + 2b) - (a - 2b)(a - 2b) =
a^2 + 4ab + 4b^2 - (a^2 - 4ab + 4b^2) =
a^2 + 4ab + 4b^2 - a^2 + 4ab - 4b^2 =
8ab + 8b^2
Ответ: 8ab + 8b^2