1) A = 5 / 4 - 2 / 3 x 9 / 16 = 5 / 4 - (2 x 9) / (3 x 16) = 5 / 4 - (2 x 3 x 3) / (3 x 2 x 8) = 5 / 4 - 3 / 8 = (5 x 2) / (4 x 2) - 3 / 8 = 10 / 8 - 3 / 8 = (10 - 3) / 8 = 7 / 8
2) B = (16 x 10^-5 x 3 x 10^4) / (24 x 10^-3) = (16 x 3 x 10^-5+4) / (24 x 10^-3) = (48 x 10^-1) / (24 x 10^-3) = (48 / 24) x (10^-1 / 10^3) = 2 x 10^-1+3 = 2 x 10^2 = 200
3) A = 21 / 24 (on peut simplifier par 3) = (21 / 3) / (24 / 3) = 7 / 8
Lista de comentários
1) A = 5 / 4 - 2 / 3 x 9 / 16
= 5 / 4 - (2 x 9) / (3 x 16)
= 5 / 4 - (2 x 3 x 3) / (3 x 2 x 8)
= 5 / 4 - 3 / 8
= (5 x 2) / (4 x 2) - 3 / 8
= 10 / 8 - 3 / 8
= (10 - 3) / 8
= 7 / 8
2) B = (16 x 10^-5 x 3 x 10^4) / (24 x 10^-3)
= (16 x 3 x 10^-5+4) / (24 x 10^-3)
= (48 x 10^-1) / (24 x 10^-3)
= (48 / 24) x (10^-1 / 10^3)
= 2 x 10^-1+3
= 2 x 10^2
= 200
3) A = 21 / 24 (on peut simplifier par 3)
= (21 / 3) / (24 / 3)
= 7 / 8
B = 2 x 10^2
= 200
Donc ces réponses semblent satisfaisantes.
Voilà j'espère avoir pu t'aider ^^