Ex44:
f(x) = ax
6a = 5
a = 5/6
f(x) = 5/6 x
g(x) = ax
-4a = 8/7
a = -2/7
g(x) = -2/7 x
h(x) = ax
2a/3 = 5
a = 15/2
h(x) = 15/2 x
Ex45:
a) h(20) = 4 h(5) = 36
b) h(2.5) = h(5) /2 = 4.5
c) h(17.5) = 7 h(5) /2 = 63/2 = 31.5
Ex46:
a) f fonction lineaire car 0 kg de fromage coute 0 €
b)
masse x 0 1 2.5 3 1.6
prix f(x) 0 12 30 36 19.2
c) f(5) = 60 signifie le prix de 5 kg de fromage