1)
y^3 + 3y^2 - y - 3 = 0
y^2(y + 3) - 1(y + 3) = 0
(y^2 - 1)(y + 3 ) = 0
y^2 - 1 = 0
y^2 = 1
y1 = - 1;
y2 = 1
y + 3 = 0
y3 = - 3
Ответ
- 3; - 1 ; 1
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2)
(x - x1)/(x2 - x1) = (y - y1)/(y2 - y1)
(x - 2)/(- 4) = (y - 1)/(- 4)
(x - 2)/ 4 = (y - 1)/4
4(x - 2) = 4(y - 1)
y - 1 = x - 2
y = x - 1