Réponse :Bonsoir,
Exercice 3
K = a² - 2a - a + 2 = a² - 3a + 2
L = 10x² + 8x - 25x - 20 = 10x² - 17x - 20
M = 3x - 3x² - 4 + 4x = -3x² + x - 4
N = -2y + 2y² + 3 - 3y = 2y² - 5y + 3
O = 6x² - 24x - 10x + 40 - (7x² + 42x + 2x + 12) = 6x² - 24x - 10x + 40 - 7x² - 42x - 2x - 12 = -x² -78x +28
Exercice 4 :
1. P = 2x² - 3x + 2x - 3 - (x² + 2x + 1) = 2x²-x - 3 - x² - 2x - 1 = x² - 3x - 4
2. Q = 6x² - 24x - 2x + 8 + 24x² - 28x + 96x - 112 = 30x² + 42x - 104
3. R = 10x² - 15x - 14x + 21 - 6x + 9 = 10x² - 35x + 30
4. S = x- 1 + 2x - 2 - (x² - x - 3x + 3) = x-1+2x-2-x²+x+3x-3= -x² + 7x - 6
Exercice 5.
1. U = 4x² - 12x + 9
2. V = 9x² + 30x + 25
3. W = 9x² - 49y² (a-b)(a+b)=a² - b²
4. X= 9x² - 30xt + 25t²
5. Y = 49x² + 60xz + 25z²
6. Z = 16ab + 20ab - 20b² - 25b² = 36ab - 45b²
