Svp pouvez m’aider pour les deux j’en comprend vraiment rien . Je suis en 3 eme

Réponse : Bonjour,

Exercice 14

a. f(2) = 8*2 = 16

f(-3) = 8 * -3 = -24

f(0) = 8*0 = 0

b. l'image de -5 par la fonction f(-5) = 8*-5 = -40

f(1/8) = 8*1/8 = 8/8 = 1

c. On pose 8x = -16

x = -16/8 = -2

On pose 8x = 0

x = 0/8=0

On pose 8x = 28

x = 28/8 = 3.5

Exercice 15

a. g(5) = 5*5 +1 = 26

b. g(0) = 5*0 +1 = 1

g(-2.1) = 5*-2.1 +1 = -10.5 + 1 = -9.5

g(7) = 5*7 + 1 = 35 +1 = 36

c. On pose 5x +1 = 21

5x = 20

x = 20/5 = 4

On pose 5X+1 = -14

5x = -14-1

5x = -15/5 = -3

On pose 5x + 1 = 0

5x = -1

x = -1/5