Упростить (2a+b) ^2-9 (a+b) ^2 Разложить на множители ((x-3) ^2-1)

1.

(2 * a + b) ^2 - 9 * (a + b) ^2 = (2 * a + b) ^2 - 3^2 * (a + b) ^2 = (2 * a + b) ^2 - [3 * (a + b) ]^2 = [2 * a + b - 3 * (a + b) ] * [2 * a + b + 3 * (a + b) ] = (2 * a + b - 3 * a - 3 * b) * (2 * a + b + 3 * a + 3 * b) = (-a - 2 * b) * (5 * a + 4 * b) = - (5 * a + 4 * b) * (a + 2 * b).

2.

(x - 3) ^2 - 1 = (x - 3 + 1) * (x - 3 - 1) = (x - 2) * (x - 4)