5cos^2x+4sinx cos x-sin^2x=0 - №23709848

5cos^2x+4sinx cos x-sin^2x=0
- Предмет:
  Математика
- Автор:
  gavenbpg8
- 6 лет назад

Ответы 1

делим всё это на cos^2 (x) ОДЗ: cosx неравно 0
получается tg^2 (x)-4tgx-5=0
Корни 5;-1
Значит: x1=-(п/4)+пk
x2=arctg (5)+пk
- Автор:
  zayne
- 6 лет назад
- 0
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