Réponse :
programme 1
x = 7 x = -4 x = 0
7 - 3 = 4 -4 - 3 = - 7 0 - 3 = -3
4 x 2 = 8 -7 x 2 = -14 -3 x 2 = -6
programme 2
x = 7 x = -4
7 + 6 = 13 -4 + 6 = 2
13 x -1 = -13 2 x -1 = -2
-13 + (7 x 3 ) = -13 + 21 = 8 -2 + ( -4 x 3 ) = -2 + -12 = -14
x=0
0 + 6 = 6
6 x -1 = -6
-6 + ( 0 x 3) = -6
Les deux programmes donnent les même résultats.
(x - 3 ) x 2 c'est 2 ( x -3 ) = 2x - 6
-1 ( x + 6 ) + 3x = -x - 6 + 3x = 2x - 6
