Răspuns:
Explicație pas cu pas:
6.
n = 4/3 - 4/3 *[4/3 - (3/9)^2] : 44/9
= 4/3 - 4/3*(4/3 - 1/9) * 9/44
= 4/3 - 4/3*(12/9 - 1/9)*9/44
= 4/3 - 4/3*11/9*9/44
= 4/3 - 1/3 = 3/3 = 1, numar natural
7.
a)
x + 3 = 7 ⇒ x = 7 - 3 = 4
x + 3 = -7 ⇒ x = -7 - 3 = -10
x = {-10, 4}
b)
-4 ≤ 3y - 2 ≤ 4
-2 ≤ 3y ≤ 6
-2/3 ≤ y ≤ 2
x = {0, 1, 2}
