X ^ 4 - 4x ^ 2 - x ^ 2 + 4 = 0

Уравнение: x^4 - 4x^2 - x^2 + 4 = 0 Simplify first: x^4 - 5x^2 + 4 = 0 Let y = x^2: y^2 - 5y + 4 = 0 Factor: (y - 4)(y - 1) = 0 y = 4 or y = 1 Replace y with x^2: x^2 = 4 or x^2 = 1 x = 2, x = -2, x = 1, x = -1