а) (x - 3)⁴ - 5(x - 3)² + 4 = 0
t = (x - 3)²
t² - 5t + 4 = 0
t² - t - 4t + 4 = 0 (Теорема Виета)
t(t - 1) - 4(t - 1) = 0
(t - 1)(t - 4) = 0
t₁ = 1; t₂ = 4
(x - 3)² = 1 (x - 3)² = 4
x - 3 = ±1 x - 3 = ±2
x₁ = 4; x₂ = 2; x₃ = 5; x₄ = 1
б) (x² - 5x - 2)² + 4x² - 20x - 40 = 0
(x² - 5x - 2)² + 4x² - 20x - 8 - 32 = 0
(x² - 5x - 2)² + 4(x² - 5x - 2) - 32 = 0
t = x² - 5x - 2
t² + 4t - 32 = 0
t² - 4t + 8t - 32 = 0
t(t - 4) + 8(t - 4) = 0
(t - 4)(t + 8) = 0
t₁ = 4; t₂ = -8
x² - 5x - 2 = 4 x² - 5x - 2 = -8
x² - 5x - 2 - 4 = 0 x² - 5x - 2 + 8 = 0
x² - 5x - 6 = 0 x² - 5x + 6 = 0
x² + x - 6x - 6 = 0 x² - 2x - 3x + 6 = 0
x(x + 1) - 6(x + 1) = 0 x(x - 2) - 3(x - 2) = 0
(x + 1)(x - 6) = 0 (x - 2)(x - 3) = 0
x₁ = -1; x₂ = 6; x₃ = 2; x₄ = 3
г) (x - 4)(x + 2)(x + 8)(x + 14) = 1204
Понятия не имею как решать. прости
b1q + b1q^2 = 14 разделим первое уравнение на 2-е
(1 + q^3)/(q +q^2) = -7/2
(1+q)(1 -q +q^2)/q(1 +q) = -7/2
(1 -q +q^2) /q = -7/2
2(1 - q +q^2) = -7q
2 -2q +2q^2 +7q = 0
2q^2 +5q +2 = 0
D = b^2 -4ac = 25 -16 = 9
q1= -1/2, a) b1 + b1q^3 = -49 б) q2 =-2 b1 + b1q^3 = -49
b1 +b1*(-1/8) = -49 b1 + b1*(-8) = -49
7/8 b1 = -49 -7b1 = -49
b1 = -49: 7/8= -49*8/7= =56 b1 = 7
а) (x - 3)⁴ - 5(x - 3)² + 4 = 0
t = (x - 3)²
t² - 5t + 4 = 0
t² - t - 4t + 4 = 0 (Теорема Виета)
t(t - 1) - 4(t - 1) = 0
(t - 1)(t - 4) = 0
t₁ = 1; t₂ = 4
(x - 3)² = 1 (x - 3)² = 4
x - 3 = ±1 x - 3 = ±2
x₁ = 4; x₂ = 2; x₃ = 5; x₄ = 1
б) (x² - 5x - 2)² + 4x² - 20x - 40 = 0
(x² - 5x - 2)² + 4x² - 20x - 8 - 32 = 0
(x² - 5x - 2)² + 4(x² - 5x - 2) - 32 = 0
t = x² - 5x - 2
t² + 4t - 32 = 0
t² - 4t + 8t - 32 = 0
t(t - 4) + 8(t - 4) = 0
(t - 4)(t + 8) = 0
t₁ = 4; t₂ = -8
x² - 5x - 2 = 4 x² - 5x - 2 = -8
x² - 5x - 2 - 4 = 0 x² - 5x - 2 + 8 = 0
x² - 5x - 6 = 0 x² - 5x + 6 = 0
x² + x - 6x - 6 = 0 x² - 2x - 3x + 6 = 0
x(x + 1) - 6(x + 1) = 0 x(x - 2) - 3(x - 2) = 0
(x + 1)(x - 6) = 0 (x - 2)(x - 3) = 0
x₁ = -1; x₂ = 6; x₃ = 2; x₄ = 3
г) (x - 4)(x + 2)(x + 8)(x + 14) = 1204
Понятия не имею как решать. прости