Предмет: Алгебра, автор: nurlanonru

3^2х+4·3^х-5 = 0 показательные уравнения

Ответы

Автор ответа: Soulfly1

Введем новую переменную 3^x=a, тогда уравнение примет вид: a²+4a-5=0
Д=4²-4*1*(-5)=16+20=36, a1=-4+6/2=1, a2=-4-6/2=-5

1) 3^x=1 2)3^x=-5 (решений нет)
x=0

Ответ: х=0.

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