Factoriser 3x + 15 = ? 3x(x + 1) + 5(x + 1) = ?.

Présentation au sujet: "Factoriser 3x + 15 = ? 3x(x + 1) + 5(x + 1) = ?."— Transcription de la présentation:

1 Factoriser 3x + 15 = ? 3x(x + 1) + 5(x + 1) = ?

2 Calcul 1 3(3x + 8) + 8x(3x + 8)

3 Calcul 2 10 – 5x

4 Calcul 3 9 – 18x

5 Calcul 4 x² + x

6 Calcul 5 8x² – 3x

7 Prêt pour la correction…

8 Calcul 1 3(3x + 8) + 8x(3x + 8)

9 Calcul 1 3(3x + 8) + 8x(3x + 8) a x k b x k

10 Calcul 1 3(3x + 8) + 8x(3x + 8) = (3x + 8)(3 + 8x)

11 Calcul 2 10 – 5x

12 Calcul 2 10 – 5x = 5 x 2 – 5 x x

13 Calcul 2 10 – 5x = 5 x 2 – 5 x x

14 Calcul 2 10 – 5x = 5 x 2 – 5 x x = 5 (2 – x)

15 Calcul 3 9 – 18x

16 Calcul 3 9 – 18x = 9 x 1 – 9 x 2x

17 Calcul 3 9 – 18x = 9 x 1 – 9 x 2x

18 Calcul 3 9 – 18x = 9 x 1 – 9 x 2x = 9(1 – 2x)

19 Calcul 4 x² + x

20 Calcul 4 x² + x = x x x + x x 1

21 Calcul 4 x² + x = x x x + x x 1

22 Calcul 4 x² + x = x x x + x x 1 = x (x + 1)

23 Calcul 5 8x² – 3x

24 Calcul 5 8x² – 3x = x x 8 x – x x 3

25 Calcul 5 8x² – 3x = x x 8 x – x x 3

26 Calcul 5 8x² – 3x = x x 8 x – x x 3 = x(8x – 3)

27 1. (3x + 8)(3 + 8x) 2. 5 (2 – x) 3. 9(1 – 2x) 4. x (x + 1) 5. x(8x – 3)