1) (x^2 - 1)(x^2 + 3) = (x^2 + 1)^2 + x
x^4 + 3x^2 - x^2 - 3 = x^4 + 2x^2 + 1 + x
x^4 + 2x^2 - 3 = x^4 + 2x^2 + x + 1
x^4 + 2x^2 - 3 - x^4 - 2x^2 - x - 1 = 0
- x - 4 = 0
- x = 4
x = - 4
Ответ
- 4
2) 4y^3 - 25y = 0
y (4y^2 - 25) = 0
y (2y - 5)(2y + 5) = 0
y = 0 ;
2y - 5 = 0 ==> y = 2,5
2y + 5 = 0 ==> y = - 2,5
Ответ
- 2,5 ; 0 ; 2,5
3) (6x - 1)^2 - (3x - 5)^2 = 0
(6x - 1 - 3x + 5)(6x - 1 + 3x - 5) = 0
(3x + 4)(9x - 6) = 0
3x + 4 = 0
3x = - 4
x = - 4/3;
9x - 6 = 0
9x = 6
x = 2/3
Ответ
- 4/3; 2/3