bonjour
[tex]A = - 2/3 + 3 /4 \\A = - 8/12 + 9/12\\A = 1 /12 \\\\B = 4/7 - ( 2 /7 + 1/5)\\B = 20/35 - ( 10/35 + 7/35)\\B = 20/35 - 17/35\\B = 3 /35 \\[/tex]
[tex]C = 4 /7 * - 3 /2\\C = - 12/14\\C = - 6/7 \\\\D = - 1 /3 x 8/3\\D = - 8/9\\\\[/tex]
[tex]- 2/3 * ( 1/2 - 1 /4) \\- 2/3 * ( 2/4 + 1/4) \\- 2/3 * 3/4\\= - 6/12\\= - 1 /2[/tex]
[tex]( - 2 /7 + 5 /42) * ( 5 - 3 /8 ) \\= ( - 12/42 + 5 /42) * ( - 15/8 ) \\= - 7/42 * - 15/8\\= 105/336\\= 5 /16[/tex]
