Question

Упростить выражения 1.3a(a-2) -2a(a-3) 2. 5b(b-c) +c(2b-c) 3. (2x+5)(4+3x) 4.(1-a) (5a+6) 5.(2x-y) (3y-4x) 6.(a-b) ²-a(a+2b) 7. 4c(c-2) -(c-4) ²

Answer 1

Вот решения данных выражений

Answer 2

1. 3a(a-2) - 2a(a-3) = 3a² - 6a - 2a² + 6a = a²

2. 5b(b-c) + c(2b-c) = 5b² - 5bc + 2bc - c² = 5b² - 3bc - c²

3. (2x+5)(4+3x) = 8x + 12x + 20 + 15x² = 27x² + 20x + 20

4. (1-a) + (5a+6) = 1 - a + 5a + 6 = 4a + 7

5. (2x-y) + (3y-4x) = 2x - 4x - y + 3y = -2x + 2y

6. (a-b)² - a(a+2b) = (a² - 2ab + b²) - (a² + 2ab) = a² - 2ab + b² - a² - 2ab = -4ab + b²

7. 4c(c-2) - (c-4)² = 4c² - 8c - (c² - 8c + 16) = 4c² - 8c - c² + 8c - 16 = 3c² - 16