Sagot :
Bonjour
calculer À :
on va faire étape par étape :
2/3 + 4/5 = (2 x 5)/(3 x 5) + (4 x 3)/(5 x 3)
2/3 + 4/5 = 10/15 + 12/15
2/3 + 4/5 = 22/15
1/(22/15) = 1 x 15/22 = 15/22
4 + 15/22 = (4 x 22)/22 + 15/22
4 + 15/22 = 88/22 + 15/22
4 + 15/22 = 103/22
7/(103/22) = 7 x 22/103
7/(103/22) = 154/103
3 - 154/103 = (3 x 103)/103 - 154/103
3 - 154/103 = 309/103 - 154/103
3 - 154/103 = 155/103
ensuite on calcule le numérateur :
-4 + 7/4 = (-4 x 4)/4 + 7/4
-4 + 7/4 = -16/4 + 7/4
-4 + 7/4 = -9/4
1/7 - 9 = 1/7 - (9 x 7)/7
1/7 - 9 = 1/7 - 63/7
1/7 - 9 = -62/7
-62/7 / (-9/4) = -62/7 x (-4/9)
-62/7 / (-9/4) = (62 x 4)/(7 x 9)
-62/7 / (-9/4) = 248/63
9/2 / 5 = 9/2 x 1/5
9/2 / 5 = 9/10
2 - 9/10 + 248/63
= (2 x 63 x 10)/630 - (9 x 63)/(10 x 63) + (248 x 10)/(63 x 10)
= 1260/630 - 567/630 + 2480/630
= 3173/630
A = (3173/630) / (155/103)
A = 3173/630 x 103/155
A = (3173 x 103)/(630 x 155)
A = 326819/97650