Réponses

2013-12-10T18:08:22+01:00
 3x-4<5(x-1)
3x-4-5(x-1) < 0

3x-4-5x+1<0
-2x-3 < 0

-2x < 3

x < -1,5
Attention! 3x-4-5(x-1) < 0 ==> 3x-4-5x+5
2013-12-10T18:13:28+01:00
3x-4<5(x-1)
3x-4<5x-5
-4+5<5x-3x
1<2x
1/2<x
x>1/2
On vérifie en prenant x=1:
3-4<5-5
-1<0