Найдите промежутки убывания функции f(x) = -x^3+9x^2+21x - №19068127

Найдите промежутки убывания функции f(x) = -x^3+9x^2+21x
- Предмет:
  Математика
- Автор:
  isaacmytn
- 6 лет назад

Ответы 1

f`(x)=-3x²+18x+21=-3(x²-6x-7)=0x1=x2=6 U x1*x2=-7x=-1 x=7 _ + _-------------------(-1)------------------(7)---------------------убыв убывx∈(-∞;-1) U (7;∞)
- Автор:
  teodora
- 6 лет назад
- 0
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MODERN CRIME
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