-
прямоугольный треугольник. дана гипотенуза - 9см и угол между гипотенузой и катетом равен 60 град, найти этот катет
Ответы 1
-
дано: треуг. АВС <С=90° <ВАС=60° АВ=9 см_____________найти: АС-?Решение: <АВС=90°-60°=30°;<АВС =30° противолежащей угол катету АС, тогда АС =АВ÷2=9÷2=4,5(см).
-
Автор:
kiki0hpo - 6 лет назад
-
0
-
-
Добавить свой ответ
Еще вопросы
-
Чтобы сварить 3 л варенья нужно 3кг 500 г клубники .сколько клубники нужно чтобы сварить 48 л варенья?
-
Предмет:
Математика -
Автор:
rodney - 6 лет назад
-
Ответов:
1 -
Смотреть
-
-
Помогите перевести текст
FUTURE OF RAILWAYS
Until recently many people were of the opinion that the railways had reached
the limit of their improvement. Yet the Japanese and French railways were the
first to prove that they were wrong. In these countries trains are normally run at
speeds of 240-270 km/hr, while in the FRG the Experimental High Speed train ICE
reached a record speed of 406 km/hr. All this caused a dramatic change in favour
of the railways. It was for the first time that passengers are preferring the train to
the plane. This experience is now made use of in many countries.
The drive for effective ways of developing railways is going on in an ever
growing number of countries. Many railway lines in Russia handle 100 and even
more trains a day. In Russia on an average the annual tonnage of lines of the
network is 26 million gross tons per kilometer of tracks. The through-put capacity
of modern large classification yards in Canada, the FRG and in a number of other
countries is as high as 8000-10000 wagons per day. In the USA running 20000 ton
trains has become normal practice. The railway networks of Asia and African
countries are expanding. Automating and mechanizing of basic operations have
become standard practice on most of the railways.
In the eighties and nineties of the last century many countries of Europe and
America celebrated the 150th anniversary of their railways. Among railway
experts the historical aspects of railways have arouse great interest. The railways
have passed through the period of accelerated expansion of the railway networks,
that was a period when 20000 km of lines were built every year. Over the last 30
years the mileage of railway networks even shrank. Super steam locomotives
rated at 5000 h.p. and developing a pressure of 15 to 16 bars were replaced by
electric and diesel electric locomotives.
The carrying capacity of wagons increased constantly and the mass of rails
went up steadily as well. Automatic brakes and the automatic coupling have
become an indispensable part of rolling stock designs. Modern passenger coaches
have become more comfortable and spacious.
What will come next? What are the railways in the XXIst century?
Forecasts are always of a relative nature. Yet, it will not run any risk of
committing a mistake when saying that the railways still have a long life to live.
What is needed is to keep pace with time, that is the railways have to make use of
all most modern scientific and technical achievements.
-
Предмет:
Английский язык -
Автор:
pancracioexqh - 6 лет назад
-
Ответов:
1 -
Смотреть
-
-
В треугольнике BCD известно, что BC = CD,CD = BD. Найдите ∠CDB. Ответ дайте в градусах
-
Предмет:
Геометрия -
Автор:
julissalyons - 6 лет назад
-
Ответов:
1 -
Смотреть
-
-
Write what you /your friends have /don't have to do every day.Example:I have to go to school every weekday,but l don't have to go to school on Saturday and Sunday
-
Предмет:
Английский язык -
Автор:
ivan923 - 6 лет назад
-
Ответов:
0 -
Смотреть
-
Топ пользователей
-
Fedoseewa27
35934 -
Devilian
2792 -
Pikachu
2228 -
hobbesbowers
2116 -
kaylynnbarron676
1818 -
女fei
1240 -
yulia-kaplina
1158 -
Poinntt
946 -
Bars
930 -
Queenmagic18
770
How much to ban the user?
1 hour
1 day
100 years