Identités remarquables : introduction Les 3 identités remarquables

Présentation au sujet: "Identités remarquables : introduction Les 3 identités remarquables"— Transcription de la présentation:

1 Identités remarquables : introduction Les 3 identités remarquables

2 Activité (3x + 4)(3x - 4) (5x + 3)² (6x - 5)² (3x + 7)²

3 (3x + 4)(3x - 4) = 9x² -12x + 12x -16 = 9x² - 16
Calculer (3x + 4)(3x - 4) (3x + 4)(3x - 4) = 9x² -12x + 12x -16 = 9x² - 16

4 Calculer (5x + 3)² (5x + 3)  (5x + 3) 25x² = + 15x + 15x +9 = 25x² + 30x +9

5 Calculer (6x - 5)² (6x - 5)  (6x - 5) = 36x² - 30x - 30x +25 = 36x² - 60x +25

6 Calculer (3x + 7)² (3x + 7)  (3x + 7) = 9x² + 21x + 21x +49 = 9x² + 42x + 49

7 (4x + 5)(4x - 5) = 16x² -20x + 20x -25 = 16x² - 25
Calculer (4x + 5)(4x - 5) (4x + 5)(4x - 5) = 16x² -20x + 20x -25 = 16x² - 25

8 Calculer (6x + 4)² (6x + 4)  (6x + 4) 36x² = + 24x + 24x +16 = 36x² + 48x +16

9 Calculer (4x + 5)² (4x + 5)  (4x + 5) 16x² = + 20x + 20x +25 = 16x² + 40x +25

10 Calculer (1 + 6x)² (1 + 6x)  (1 + 6x) 1 = + 6x + 6x +36x² = 1 + 12x + 36x²

11 Calculer (1 - 5x)² (1 - 5x)  (1 - 5x) 1 = - 5x - 5x +25x² = 1 - 10x + 25x²

12 = 36 -30x + 30x -25x² = 36 - 25x² Calculer (6 + 5x)(6- 5x)

13 (3x + 4)(3x - 4) = 9x² - 16 (5x + 3)² = 25 x² + 30x + 9 (6x - 5)² = 36 x² - 60x + 25 (3x + 7)² = 9 x² + 42x + 49 (4x + 5)(4x - 5) = 16x² - 25 (6x + 4)² = 36 x² + 48x + 16

14 (3x + 4)(3x - 4) = 9x² - 16 (5x + 3)² = 25 x² + 30x + 9 (6x - 5)² = 36 x² - 60x + 25 (3x + 7)² = 9 x² + 42x + 49 (4x + 5)(4x - 5) = 16x² - 25 (6x + 4)² = 36 x² + 48x + 16

15 (3x + 4)(3x - 4) = 9x² - 16 (5x + 3)² = 25 x² + 30x + 9 (6x - 5)² = 36 x² - 60x + 25 (3x + 7)² = 9 x² + 42x + 49 (4x + 5)(4x - 5) = 16x² - 25 (6x + 4)² = 36 x² + 48x + 16

16 Calculer (a + b)² (a + b)² (a + b)(a + b) = a² = + ab + ab +b² a² = + 2ab +b²

17 Calculer (a - b)² (a - b) (a - b) (a - b)² = = a² - ab - ab +b² = a² - 2ab +b²

18 Calculer (a + b)(a - b) (a + b) (a - b) = a² - ab + ab -b² = a² - b²

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