Упростим выражения
<span>(8b−8)</span><span>(8b+8)</span>−8b<span>(8b+8)=(8b+8)(8b-8-8b)=(8b+8)*(-8)=-64b-64
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При b=2.6
-64*2.6-64=-166.4-64= <u><em>-230.4</em></u>
3ab(2a² + 3b²) - 4ab(b² - a²) = ab(6a²+ 9b² - 4b² + 4a²) =
= 5ab(2a² + b²) = 5 · (-2) · (2 · 4 + 1) = -90
Log₃ (x² - 4x + 4) = 2
x² - 4x + 4 = 9
x² - 4x - 5 = 0
По теореме Виета:
x₁ = -1
x₂ = 5
3log₄ x = log₄ 12,5 + log₄ 64
log₄ x³ = log₄ 800
x³ = 800
x = 2
2log₃ (x-2) - log₃ (x+1) = 1
log₃ (x-2)² - log₃ (x+1) = 1
log₃ (x-2)² = log₃ 3 + log₃ (x+1)
log₃ (x-2)² = log₃ 3(x+1)
x² - 4x + 4 = 3x + 3
x² - 7x + 1 = 0
D = (-7)² - 4 = 45
x₁ =
x₂ =
<span>log₄ (x-4) + log₄ (x+4) = log₄ (3x+2)
</span>log₄ (x-4)(x+4) = log₄ (3x+2)
x² - 16 = 3x+2
x² - 3x - 18 = 0
По теореме Виета:
x₁ = -3
x₂ = 6