Réponse :
Explications étape par étape
1)
x --- (-3)* ---> -3x --- +2 ---> f(x) = -3x+2
2)
f(-1) = (-3)(-1)+2=3+2 = 5
image de 3 = f(3) = (-3).3 + 2 = -7
f(1/9) = -3/9 + 2 = 2 - 1/3 = 5/3 = 1,67 (environ)
[tex]f(\sqrt2)=-3\sqrt2+2\\f(\sqrt2)=2-3\sqrt2\approx-2,24[/tex]
3)
f(x) = 2 ==> -3x+2 = 2 ==> -3x = 0 ==> x=0
f(x) = 1 ==> -3x+2 = 1 ==> -3x = -1 ==> x=1/3
f(x) = 5 ==> -3x+2 = 5 ==> -3x = 3 ==> x=-1
