Предмет: Алгебра, автор: Аноним

Выбрать уравнение, которое не имеет действительных корней
Выберите правильный ответ:

x^2+4x−3=0

x^2−4x+5=0

x^2−8x−9=0

4x^2+4x+11=0

16x^2+8x+1=0

Ответы

Автор ответа: nikita000999
1
2,4-т.к. дискриминант отрицательный. 
Дискриминант рассчитывается по формуле:
D=корень из(b^2-4ac);
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