х^4 + х^2 - 2 = 0
x^2 = t (>= 0)
t^2 + t - 2 = 0
D = 1 + 8 = 9
t12 =(-1 +- 3)/2 = -2 1
t1 = -2 нет < 0
t2 = 1
x^2 = 1
x12 = +- 1
ответ -1, 1
х^4 + х^2 - 2 = 0
x^2 = t (>= 0)
t^2 + t - 2 = 0
D = 1 + 8 = 9
t12 =(-1 +- 3)/2 = -2 1
t1 = -2 нет < 0
t2 = 1
x^2 = 1
x12 = +- 1
ответ -1, 1