Réponses

Meilleure réponse !
2014-04-10T21:49:25+02:00
Ouii je veux bien et c'est trop facile :)
ex 7
1+1/2 = 1×2/1×2 + 1/2 = 2/2 + 1/2 = 3/2
2/3 + 1 = 2/3 + 1/1 = 2/3 + 1×3 / 1×3 = 2/3 + 3/3 = 5/3
1-3/4 = 1/1 - 3/4 = 1×4 / 1×4 - 3/4 = 4/4 - 5/4 = 1/4
8/ 7 - 1 = 8/7 - 1 / 7 = 8/ 7 - 1×7 / 1×7 = 8/7 - 7/ 7 = 1/7
ex 8
2+ 1/3 = 2/ 1 + 1/3 = 2×3 / 1×3 + 1/ 3 = 6 / 3 + 1/3 = 7
3/7 + 4 = 3/7 + 4/1 = 3/7 + 4×7 / 1×7 = 3/7 + 28 / 7 = 31/7
5-3/5 = 5/1 - 3/5 = 5×5 / 1× 5 - 3/5 = 25/5 - 3/5 = 22/5
9/4 - 2 = 9/4 - 2/1 = 9/4 - 2/1 = 9/4 - 2×4 / 1×4 = 9/4 - 8 / 4 = 1/4
ex 9
2/3 + 4/3 + 7/ 3 = 2+4+ 7 / 3 = 13 / 3
3/7 + 4/7 - 5 / 7 = 3+-1 / 7 = 2 / 7
17/ 12 - 1/3 - 3/4 = -17 / 12 - 1×4 / 3×4 - 3×3 / 4×3 = 17 / 12 - 4/12 - 9 / 12 = 4/12 = 4×1 / 4×3 = 1/ 3
2/5 - 3/10 + 7/10 = 2×2 / 5×2 - 3/10 + 7/10 = 4/10 - 3/ 10 + 4/10
= 5/10 = 5×1 / 5×2 = 1 / 2
ex 10
5/4 + 1/12 + 3/4 = 5 × 3 / 4×3 + 1/2 + 3×3 / 4×3 = 15 / 12 - 1/12 + 9 / 12 = 25/12
1 + 1/2 - 3/4 = 1/1 + 1/2 - 3/4 = 1×4 / 1×4 + 1×2 / 2x2 - 3 / 4 = 4/4 + 2/4 - 3 / 4 = 6- 3 / 4 = 3/4
17/15 - (4/5 + 2/15 ) = 17/15 - ( 4×3 / 5×3 + 2/15 ) = 17/15 + (- 4/5 -2 / 15 ) = 17/15 + ( - 4x3 / 5×3 - 2/15) = 17/ 15 + (-12 /15 - 2 / 15 ) = 17/15 + -14/15 = 3/15 = 3×1 / 3×5 = 1/5
4/3 - (11/9 - 2 / 3 ) = 4/3 + ( - 11/9 + 2 / 3 ) = 4/3 + ( - 11/9 + 2/3 ) = 4/3 + ( - 11/9 + 2×3 / 3×3 ) = 4/3 + ( -11/9 + 6/ 9 ) = 4/3 + 5/9 = 4×3 / 3×3 - 5/9 = 12/ 9 - 5/9 = 7/9

ps : / = aux fractions dsl j'ai pas la touche j'espère que tu comprendra c'est très long a faire :)