bonjour
f ( - 1 ) = 5 et f ( 2 ) = - 4
( - 4 - 5 ) / ( 2 + 1 ) = - 9/3 = - 3
ax = - 3 x
f ( -1) = 5
- 1 * - 3 + b = 5
b = 5 - 3 = 2
f (x) = - 3 x + 2
x - 6 - 1 0 1/3 2 5 47
f (x) 20 5 2 1 - 4 - 13 - 139
