Réponse :
A = (-x + 3)(4x - 4) + 16x² - 16
1. A = -4x² + 4x + 12x - 12 + 16x² - 16 = 12x² + 16x - 28
2. A = 2(6x² + 8x - 14)
3. A(-3) = 2[(6*-3) + (8*-3) - 14] = 2[(-18) + (-24)] = 2(-42) = -84
A(10) = 2[(6*10) + (8*10) - 14] = 2(60 + 80 - 14) = 2(126) = 252
4. A = 0
A = 12x² + 16x - 28 = 0
12x² + 16x - 28 = 0
*12x² = -16x + 28
x² = (-16x/12 + 28/12 = (-8x*2)/(6*2) + (2*14)/(2*6) = -8x/6 + 14/6 = (-4x*2)/(3*2) + (7*2)/(3*2) = -4x/3 + 7/3
x = racine carrée de (-4x/3 + 7/3)
Explications étape par étape
