Sagot :
Bonsoir,
1. A = 25+ 70x +49x²
= (5+7x) ²
2. B = 1-16x²
= (1-4x) (1+4x)
3. C = 4x² - 12x +9
= (2x -3)²
4. D = 49x² + 112x+64
= (7x +8)²
5. E= 9x² - 42x +49
= (3x - 7)²
6. F = 16-9x²
= (4-3x) ( 4+3x)
7. G = 25x² + 30x+9
= (5x +3)²
ou
(5x-3)²
si 25x² - 30x+9
8. H = 1+ 16x+64x²
= (1+8x)²
9. I = 4x² - 36
= (2x-6) (2x+6)
Bonjour,
1. A = 25 + 70x + 49x² = 5² = 2 × 5 × 7x + (7x)² = (5 + 7x)²
2. B = 1 - 16x² = 1² - (4x)² = (1 - 4x) (1 + 4x)
3. C = 4x² - 12x +9 = (2x)² - 2 × 2x × 3 + 3² = (2x - 3)²
4. D = 49x² + 112x + 64 = (7x)² + 2 × 7x × 8 + 8² = (7x + 8)²
5. E= 9x² - 42x + 49 = (3x)² - 2 × 3x × 7 + 7² = (3x - 7)²
6. F = 16 - 9x² = 4² - (3x)² = (4 - 3x) (4 + 3x)
7. G = 25x² + 30x + 9 = (5x)² + 2 × 5x × 3 + 3² = (5x + 3)²
8. H = 1 + 16x + 64x² = 1² + 2 × 1 × 8x + (8x)² = (1 + 8x)²
9. I = 4x² - 36 = (2x)² - 6² = (2x - 6) (2x + 6)