Sagot :
Réponse :
Bjr,
On a :
1)
A = 5/7 + 1/7 : (5+1/2)
A = 5/7 + 1/7 : (11/2)
A = 5/7 + 1/7 * 2/11
A = 5/7 + 2/77
A = 5*11/7*11 + 2/77
A = 55/77 + 2/77
A = 57/77
2)
B = 15*10^(-3) * 7* 10^7 : 5*10^2
B = 105*10^4/5*10^2
B = 21*10^4/10^2
B = 21*10^(4-2)
B = 21*10²
B = 2 100
3)
A = (b+2)²-(b-3)
A = b²+2*b*2+2²-(b-3)
A = b²+4b+4-b+3
A = b²+3b+7
4)
B = 3a²+6a
B = 3a*a+3a*2
B = 3a(a+2)
5)
8 = 6 - 2a
8 - 6 = - 2a
- 2a = 2
- a = 2/2
- a = 1
a = -1
J'espère avoir pu vous aider