Предмет: Математика, автор: velesn123

Помогите пожалуйста 5^2x-2*5^x-15=0

Ответы

Автор ответа: fixmix9776

Пусть 5^x=y y>1 y^2 -2y - 15=0 y1=5, y2=-3(т.к. y>1,корень не подходит) 5^х=5 5^х=5^1 х=1

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