Identités remarquables : introduction

Les 3 identités remarquables

Activité

(3x + 4)(3x - 4)

(5x + 3)²

(4x + 5)(4x - 5)

(6x - 5)²

(3x + 7)²

(6x + 4)²

Calculer (3x + 4)(3x - 4)

(3x + 4)(3x - 4)

= 9x² -12x + 12x -16

= 9x² - 16

Calculer (5x + 3)²

(5x + 3) (5x + 3)

= 25x² + 15x + 15x +9

= 25x²+ 30x +9

Calculer (6x - 5)²

(6x - 5) (6x - 5)

= 36x² - 30x - 30x +25

= 36x²- 60x +25

Calculer (3x + 7)²

(3x + 7) (3x + 7)

= 9x² + 21x + 21x +49

= 9x² + 42x + 49

Calculer (4x + 5)(4x - 5)

(4x + 5)(4x - 5)

= 16x² -20x + 20x -25

= 16x² - 25

Calculer (6x + 4)²

(6x + 4) (6x + 4)

= 36x² + 24x + 24x +16

= 36x²+ 48x +16

Calculer (4x + 5)²

(4x + 5) (4x + 5)

= 16x² + 20x + 20x +25

= 16x²+ 40x +25

Calculer (1 + 6x)²

(1 + 6x) (1 + 6x)

= 1 + 6x + 6x +36x²

= 1 + 12x + 36x²

Calculer (1 - 5x)²

(1 - 5x) (1 - 5x)

= 1 - 5x - 5x +25x²

= 1 - 10x + 25x²

Calculer (6 + 5x)(6- 5x)

(6 + 5x)(6- 5x)

= 36 -30x + 30x -25x²

= 36 - 25x²

(3x + 4)(3x - 4) = 9x² - 16

(5x + 3)² = 25 x² + 30x + 9

(4x + 5)(4x - 5) = 16x² - 25

(6x - 5)² = 36 x² - 60x + 25

(3x + 7)² = 9 x² + 42x + 49

(6x + 4)² = 36 x² + 48x + 16

(3x + 4)(3x - 4) = 9x² - 16

(5x + 3)² = 25 x² + 30x + 9

(4x + 5)(4x - 5) = 16x² - 25

(6x - 5)² = 36 x² - 60x + 25

(3x + 7)² = 9 x² + 42x + 49

(6x + 4)² = 36 x² + 48x + 16

(3x + 4)(3x - 4) = 9x² - 16

(5x + 3)² = 25 x² + 30x + 9

(4x + 5)(4x - 5) = 16x² - 25

(6x - 5)² = 36 x² - 60x + 25

(3x + 7)² = 9 x² + 42x + 49

(6x + 4)² = 36 x² + 48x + 16

Calculer (a + b)²

(a + b)² (a + b)(a + b)

= a²+ ab + ab +b²

= a² + 2ab +b²

=

Calculer (a - b)²

(a - b)² = (a - b) (a - b)

= a² - ab - ab +b²

= a² - 2ab +b²

Calculer (a + b)(a - b)

(a + b) (a - b)

= a² - ab + ab -b²

= a² - b²