Предмет: Алгебра, автор: alinakisa2

решите уравнение 7x^2+x+1=0

Ответы

Автор ответа: Vasily1975

Дискриминант уравнения D=1²-4*7*1=-27=(i*3*√3)², где i=√-1

x1=(-1+i*3*√3)/14=-1/14+1/14*i*3*√3,
x2=(-1-i*3*√3)/14=-1/14-1/14*i*3*√3.

Ответ:
x1=(-1+i*3*√3)/14=-1/14+1/14*i*3*√3,
x2=(-1-i*3*√3)/14=-1/14-1/14*i*3*√3.

Vasily1975: Но моё решение годится, если вы изучали комплексные числа. Если нет, то ответ будет другой: так как дискриминант уравнения отрицателен, то действительных решений нет.

alinakisa2: именно этого я и ждала

alinakisa2: ничего

alinakisa2: и так сойдет

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