Question

x-9 in modul +5 mai mare sau egal cu 3-4x

Answer 1

Ix-9I+5≥3-4x
Ix-9I≥-4x-5+3I(x-9I≥-4x-5
cazl I:
x-9≥-4x-5
x+4x≥9-5
5x≥4
x≥4/5
x≥0,8
x∈[0,8  +α)

cazul II
x-9≥-(-4x-5)
x-9≥4x+5
x-4x≥5+9
-3x≥14    inmultim -1
x≤-14/3
x≤-4,(6)
x∈(-α, -4,(6)]
x∈(-α, -4,(6)]u[0,8, +α)