Question

7 класс1) (2x-3)²+12xy2)(2-a)(2+a)-a²​

Answer 1

Ответ:

(2x-3)^2+12xy=4x^2-12x+9+12xy;

(2-a)(2+a)-a^2=4-a^2-a^2=4-2a^2.

Объяснение:

(a-b)^2=a^2-2ab+b^2;

(a-b)(a+b)=a^2-b^2.

Answer 2

Let's simplify the given expressions step by step:

1. (2x-3)² + 12xy

To simplify this expression, we'll expand the square and then combine like terms:

(2x - 3)² = (2x - 3)(2x - 3) = 4x² - 6x - 6x + 9 = 4x² - 12x + 9

Now, add 12xy to this expression:

4x² - 12x + 9 + 12xy

We can't simplify this expression further because the terms have different variables (x and y) and cannot be combined further.

2. (2-a)(2+a) - a²

Let's apply the difference of squares formula, which states that (a - b)(a + b) = a² - b²:

(2 - a)(2 + a) = 2² - a² = 4 - a²

Now, subtract a² from 4:

4 - a²

So, the simplified expression is 4 - a².