Предмет: Математика, автор: Gamelikesyirytv

(x²+2x)²+13(x²+2x)+12=0

Ответы

Автор ответа: andruxa82167
0
х^2 + 2х обозначаем как t
тогда
t^2 +13t +12 = 0
по теореме Виета подбираем корни
t1 + t2 = 13
t1*t2 = 12
t1 = -1
t2 = -12
1) x^2 + 2х = - 1
x^2 +2х + 1 = 0
по теореме Виета
х1 + х2 = -2
х1*х2 = 1
х1 = х2 = -1
2) х^2 + 2х = -12
х^2 + 2х + 12 = 0
дискриминант 2^2 - 4*1*12 = 4 - 48 = -44 меньше нуля. следовательно данное уравнение не имеет корней

ответ: х = -1
Автор ответа: andruxa82167
0
Я написал t1 + t2 = 13 а должно быть - 13, с минусом но считал я правильно
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