Réponses

2014-08-27T16:18:24+02:00
A= \frac{45}{8} + \frac{14}{45} * \frac{63}{56}
A=  \frac{45}{8} +  \frac{882}{2520}
 A= \frac{14175+882}{2520}
A =  \frac{239}{40}

B = \frac{ \frac{2}{3}* \frac{1}{8}  }{ \frac{5}{6}- \frac{3}{4}  }
B = \frac{ \frac{2}{24}}{ \frac{1}{12}}
B =  \frac{2}{24} *  \frac{12}{1}
B = 1

C = (-2* \frac{3}{5} +4* \frac{8}{10} )* \frac{1}{2}
C = (- \frac{6}{5} + \frac{32}{10} )* \frac{1}{2}
C = 2* \frac{1}{2}
C =  1

Bonne journée.
Merci beaucoup, bonne journée également :)
2014-08-27T16:22:18+02:00
A = 45/8 + 14/45 x 63/56
A = 45/8 + 14 x 63
                 45 x 56
A = 45/8 + 882/2520
A = 45 x 315 / 8 x 315 + 882/2520
A = 14175/2520 + 882/2520
A = 15057/2520
A = 63 x 239 / 63 x 40
A = 239/40

B = 2/3 x 1/8
      5/6 - 3/4
B =            2/24___________
   5 x 4 / 6 x 4 - 3 x 6 / 4 x 6
B =    2/24__
  20/24 - 18/24
B = 2/24
       2/24
B = 2/24 : 2/24
B = 2/24 x 24/2
B = 2 x 24
      24 x 2
B = 48/48
B = 1

C  = (- 2 x 3/5 + 4 x 8/10)  x 1/2
C = (- 2 x 34 x 8) x 1/2
           5           10
C = (-6/5 + 32/10) x 1/2
C = (- 6 x 2 / 5 x 2 + 32/10) x 1/2
C = ( - 12/10 + 32/10) x 1/2
C = 20/10 x 1/2
C = 20 x 1
      10 x 2
C = 20/20
C = 1