Réponse :
Explications étape par étape
Bonsoir
B = -4/21 x 9/-12 x -28/27
B = -(28/21 x 4/12 x 9/27)
B = -(7 x 4)/(7 x 3) x 4/(4 x 3) x 9/(9 x 3)
B = -4/3 x 1/3 x 1/3
B = -4/27
C = -11/-24 x -15/45 x 8/-55
C = 11/55 x 15/45 x 8/24
C = 11/(5 x 11) x 15/(15 x 3) x 8/(8 x 3)
C = 1/5 x 1/3 x 1/3
C = 1/45
