Réponse :
EXERCICE 1
f:x = 5x
a) f(2) = 5*2=10
b) f(x) : 5x = 50 x = 50/5 = 10
c) *f(20) = 5(20) = 100
*f(x) = 5 5x = 5 x = 5/5 = 1
EXERCICE 2
g:x = -3x
a) g(3) = -3(3) = -9
b) g(x) = 12 -3x = 12 x = 12/-3 = -4
c) *g(5) = -3(3) = -9
*g(x) = -9 -3x = -9 x = 9/3 = 3
EXERCICE 3
f:x = -4x
a) f(32) = -4(32) = -128
b) f(x) = -16 -4x = -16 x = -16/-4 = 4
c) *f(-2) = -4(-2) = 8
*f(x) = 4 -4x = 4 x = 4/-4 = -1
EXERCICE 4
f: x = 2,4x
a) f(3) = 2,4(3) = 7,2
b) f(x) = - 15 2,4x = - 15 x = -15/2,4 = -150/24 = -5/8
EXERCICE 5
f : x = -7x
a) f(-5,2) = -7(-5,2) = 36,4
b) f(x) = -49 -7x = -49 x = 49/7 = 7
EXERCICE 6
f : x = x/3
a) f(-9) = 9/3 = 3
b) f(x) = -12 x/3 = - 12 x = -12/(1/3) = -12*3 = -36
Explications étape par étape :
