Réponses

2013-11-17T16:36:59+01:00
7/12-(5/6-8/9)
=7/12-(15/18-16/18)
=7/12-(-1/18)
=21/36+2/36
=23/36

19/57-5/24
=456/1368-285/1368
=171/1368
=57/456
=19/152
=8

1-1/2+1/4-1/8+1/16
=16/16-8/16+4/16-2/16+1/16
=11/16