bonjour
f (x) = 2 x
f (0) = 0
f ( 2 ) = 4
donc d 2
g (x) = 0.5 x
g ( 2 ) = 1
g ( 0 ) = 0
donc d 3
h (x) = - 4 x
h ( 0 ) = 0
h ( - 1 ) = 4
donc d 1