Помогите!!!!!!! очень срочно нужно номер 4, пожалуйста!

Помогите!!!!!!! очень срочно нужно номер 4, пожалуйста!
- Предмет:
  Алгебра
- Автор:
  giannipetersen
- 6 лет назад

Ответы 1

Пусть скорость теплохода х, тогда "ракеты" х+50путь в 210 км ракета прошла за 210/(х+50) часов,путь в 210 км теплоход прошел за 210/х часов210/х - 210/(х+50)=7,5 часа1/x - 1/(x+50)=7.5/210 1 1 50 50 7.5-- - -------- = -------- = ---------- = -------x x+50 x(x+50) x²+50x 2107.5x²+375x-10500=0 D=140625+315000 =455625√D=675x1=1/15*(-375+675)=300/15=20 км/часx2=1/15(-375-675)<0 не годитсяскорость Ракеты равна 20+50=70 км/час
- Автор:
  diggerxlt0
- 6 лет назад
- 0
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Ambient divers, unlike divers who go underwater in submersible vehicles or
pressure resistant suits, are exposed to the pressure and temperature of the
surrounding (ambient) water. Of all types of diving, the oldest and simplest is free
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Помогите!!!!!!! очень срочно нужно номер 4, пожалуйста!

Ответы 1

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