1)a(а++а)^2 2)3(b-1)^2+8b 3)(m+4)^2-(m-3)(m+3) - вопрос №1223128342336805565 от Rookgolf60 26.05.2021 16:28

Question

Алгебра: 1)a(а++а)^2 2)3(b-1)^2+8b 3)(m+4)^2-(m-3)(m+3)

Rookgolf60 · Answer

(1) а(а + 2b) - (b + a)² = a² + 2ab - (b² + 2ab + a²) = a² + 2ab - b² - 2ab - a² = -b²
(2) 3(b - 1)² + 8b = 3(b² - 2b + 1) + 8b = 3b² - 6b + 3 + 8b = 3b² + 2b + 3
(3) (m + 4)² - (m - 3)(m + 3) = m² + 8m + 16 - (m² - 9) = m² + 8m + 16 - m² + 9 = 8m + 25