EXERCICE DE MATHS NIVEAU 3eme

1) T = 36 x – 54 + 12 + 20 x – 66 x + 42 ( développement )
T=  - 10 x
T = - 10 * 638, 529 = - 6 385, 29
2) T = (- 11 /2) * - 10 = 110 /2 = 55       ( en utilisant T = - 10  * x  trouvé en 1) )

t=6x6x638,529-6x9+4x3+4x5x638,529-6x11x638,529+6x7
t=36x638,529-54+12+20x638,528-66x638,529+42
t=638,529(36+20-66)-54+12+42
t=638,529x(-10)
t=-6385,29

2.
t=6(6x-11/2-9)+4(3+5x-11/2)-6(11x-11/2-7)
t=-6x6x11/2-6x9+4x3-4x5x11/2+6x11x11/2+6x7
t=-36x11/2-54+12-20x11/2+66x11/2+42
t=11/2(-36-20+66)-54+12+42
t=11/2(10)
t=11 x 5 = 55