( х² - 3 )² - 4 = 0
х⁴ - 6х² + 9 - 4 = 0
х⁴ - 6х² + 5 = 0
х² = t.
t² - 6t + 5 = 0
D = 36 - 4 × 1 × 5 = 36 - 20 = 16 > 0. 4.
х1 = ( 6 + 4 ) / 2 = 10/2 = 5.
х2 = ( 6 - 4 ) / 2 = 2/2 = 1.
1) х² = 5
х = ± √5.
2) х² = 1
х = ± 1.
Ответ : -√5 ; -1 ; 1 ; √5.
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