bonsoir
A = ( 8) : ( 16 : -6)
= 8 : - 4
= - 2
B = ( - 8/5) : ( -24)
= - 8/5 x - 1/24
= 8/120 = 1/15
C = manque quelque chose dans la seconde ()
inverse de A = - 1/2
inverse de B = 15
inverse de C = ?
D = 1/2 - 1/7 : 2/21
= 1/2 - 1/7 x 21/2
= 1/2 - 21/14
= 7/14 - 21/14
= - 14/14 = - 1
E = 1/3 : ( 1 + 2/3)
= 1/3 : ( 3/3 + 2/3)
= 1/3 : 5/3
= 1/3 x 3/5
= 3 /15 = 1 /5