Réponses

Meilleure réponse !
2013-11-03T19:22:26+01:00
 e = (2x-1)(x+8)+(x+8)(3x+5)
   =(2(-5/7)-1)(-5/7+8)+(-5/7+8)(3(-5/7)+5)
   =(-10/7-1)(-5/7+8)+(-5/7+8)(-15/7+5)
   =(-10/7-7/7)(-5/7+56/7)+(-5/7+56/7)(-15/7+35/7)
   =(-17/7)(51/7)+(51/7)(20/7)
   =-867/49+1020/49=153/49
2013-11-03T19:30:55+01:00
E = ( 2 x (-5/7) - 1 ) ( -5/7 + 8 ) + ( -5/7 + 8 ) ( 3 x (-5/7) + 5 )
= ( -10/7 - 1 ) x 51/7 + 51/7 x ( -15/7 + 5 )
= -17/7 x 51/7 + 51/7 x 20/7
= -867/49 + 1020/49
= 153/49