Question

Помогите решить x^4-5x^2+4=0

Answer 1

(х²-1)(х²-4)=0
(х-1)(х+1)(х-2)(х+2)=0
х=-1; x=1; x=-2; x=2

Answer 2

x⁴ - 5x² + 4 = 0
t² - 5t + 4 = 0 (замена)
D = (-5)² - 4×1×4 = 9
t = (-(-5) ± √9) ÷ 2
t₁ = 4;   t₂ = 1
x² = 4;  x² = 1

x₁ = 2; x₂ = - 2; x₃ = 1; x₄ = -1