4а+32-7а +7<span><12</span>
<span>4а-7а<span><12-32-7</span></span>
-3а <span><-27</span>
<span>а <span>→(знак больше:D) -27:(-3)</span></span>
<span><span>а <span>→ 9</span></span></span>
-3x-4/5≥0
-3x≥0.8
x≤0.8/(-3)
x≤-4/15
Решение
log₂² x - 4log₂ x + 3 = 0
ОДЗ: x > 0
log₂ x = t
t² - 4t + 3 = 0
t₁ = 1
t₂ = 3
1) log₂ x = 1
x = 2¹
x₁ = 2
2) log₂ x = 3
x = 2³
x₂ = 8