Предмет: Алгебра, автор: alina28999

не вычисляя корней х1 и х2 уравнения 2x"2+5x-3=0...найдите х1+х2+х1*х2

Ответы

Автор ответа: Soulfly1

По теореме Виета, справедливы следующие выражения для корней квадратного уравнения, вида х²+рх+q=0 : х1+х2=-р, х1*х2=q.
В нашем случае 2х²+5х-3=0 или х²+5/2x-3/2=0, где р=5/2, q=-3/2
Следовательно х1+х2=-5/2, х1*х2=-3/2, тогда х1+х2+(х1*х2)=-5/2-3/2=-4

Предыдущий вопрос

Следующий вопрос

Похожие вопросы

Предмет: Литература, автор: poiuyt29

Ревизор.Гоголь
Срочно!

1)Почему Бобчинский и Добчинский приняли Хлестакова за ревизора?

2)Какие детали фрагмента вызывают смех у читателя и зрителя? Почему?

3)На что направлена авторская ирония?
Какими способами автор передаёт волнение городничего?

4)Какие детали фрагмента вызывают смех у читателя и зрителя? Почему?

6 лет назад

Предмет: Русский язык, автор: hjgyyjiy

Решите плиз!!!!!Срочно!!!!!!!!!

6 лет назад

Предмет: Английский язык, автор: vikysyaka

Ex. 2. Вставьте слова : (a) few, (a) little.
1. Wait, I'll pick … roses for you from my garden. 2. … people could resist such a temptation. 3. The patient has made … progress in the last couple of weeks. 4. There is … progress in the business. We must take some measures to improve it. 5. —Could you give me a little information on the trip? — There is ... I can tell you, sir. It's out of the list. 6. Paul put ... coins in the slot, thought ..., and then dialed the number. 7. Let's go to the market and buy ... fruit and ... carrots. 8. There is ... furniture in our country house. We need to buy ... more things. 9. I'm still hungry. I think I'll have ... more fish. 10. When I was a child, we kept ... pigeons in our back yard. 11. If I accept that job, I'll make ... more money. 12. There are ... cars on the road today. It's Sunday. 13. Many questions were asked, but ... were answered. 14. Wait ..., there are still ... things to attend to. 15. Even now there is ... we can do to improve the weather.
Ex. 3. Напишите следующие предложения в отрицательной и вопросительной форме, внося необходимые изменения
1. There is a lot of fruit this year. 2. There are a lot of apple trees in our garden. 3. There are a lot of slang words in his vocabulary. 4. There is a lot of interesting news in today's e-mail. 5. There are a lot of things which you still don't understand. 6. There is a lot of snow in winter in Siberia. 7. There are a lot of sights in every capital. 8. There is a lot of pollution in big cities. 9. We had a lot of fun at the party. 10. There is a lot of sunny weather in Italy. 11. Helen has a lot of good ideas. 12. My elder brother helps me a lot. 13. One should have a lot of patience to catch fish. 14. English people send a lot of cards on Christmas. 15. This journalist wrote a lot of books about famous people.
Ex. 4. Вставьте слова: a lot (of), lots of, plenty of, much, many, a great deal of.
1.1 wish you all ... good luck. 2. Is there ... oil in the Caspian sea? 3. We bought ... food for the barbecue. 4. Do you have ... homework to do for Saturday? 5. — How ... exams did you have to take? — Quite .... 6. My sister drinks too ... coffee. 7. He is so fat because he eats too ... sandwiches. 8. These days people get... information from (the) Internet. 9. — Oh, Mother, I love him so .... — I think you love him too ... . 10. ... and ... refugees came to Spain and Italy. 11. There are ... daffodils in England in spring. ; 12. The earthquake caused ... damage to the country. 13. ... of the exhibition was devoted to his later works. 14. It was a big house with ...
windows. 15. — Feeling a bit better? — ..., Doctor. ... better. 16. That's happened ... a time to me. 17. The information proved useful to ... people. 18. ... happy returns of the day! 19. Thank you very ... . 20. She doesn't talk about her life ... . 21. Now I feel ... more confident. 22. It is ... less likely. 23. We've got ... time. 25. There are always ... jobs to be done. 26. Take as ... money as you need.

6 лет назад

Предмет: Математика, автор: Аноним

запишите числа противоположные числам +12, 0 ,-16

9 лет назад

Предмет: Физика, автор: angelinazhuren

какую массу бензина нужно сжечь ,чтобы получить 2,3 10(в 8 степени) Дж энергии?Удельная теплота сгорания бензина 4,6*10(в 7 степени) Джкг.

9 лет назад