bjr
ex 1
A = a³ x a⁶ x a⁷ (on ajoute les exposants : 3 + 6 + 7 = 16)
A = a¹⁶
B = x¹³ * x¹⁷ * x (x = x¹ ; 13 + 17 + 1 = 31)
B = x³¹
C = 5¹⁰ x 5⁻² x 5⁹ (10 - 2 + 9 = 17)
C = 5¹⁷
D = 2¹⁴ x 4 x 16 (4 = 2² ; 16 = 2⁴ )
D = 2¹⁴ x 2² x 2⁴ (14 + 2 + 4 = 20)
D = 2²⁰
E = 5⁵ x 25 x 5
E = 5⁵ x 5² x 5¹
E = 5⁸
ex 2
5/3 ∈ Q ; 2/8 ∈ D (2/8 = 1/4 = 0,25)
18/3 ∉ N ; 7/5 ∉ N
14 ∈ Q ; 17/7 ∉ D ; (-24) ∈ Z
(+18/9) ∈ Z ; (18/9 = 2)
-9/2 ∉ Z
ex 3
N ⊂ D ; Q ⊄ Z ; Z ⊂ D ; D ⊄ N
Q ⊄ D ; N ⊂ Q ; Z ⊂ Q ; Q ⊄ N
