Предмет:
МатематикаАвтор:
анонимДокажем тождество:
1 + cos α = (sin α + tg α)/tg α;
Упростим выражение, применяя основные тригонометрические формулы и тождества. Получаем:
1 + cos α = (sin α + sin a/cos a)/tg α;
1 + cos α = (sin α * cos a + sin a)/cos a)/tg α;
1 + cos α = (sin α * cos a + sin a)/cos a)/(sin α/cos a);
1 + cos α = (sin α * cos a + sin a)/cos a * cos a/sin α;
Сокращаем дробь в левой части выражения.
1 + cos α = (sin α * cos a + sin a)/sin α;
Вынесем в числителе общий множитель за скобки.
1 + cos α = sin a * (cos a + 1)/sin α;
1 + cos α = 1 + cos α;
Верно.
Автор:
bubbles20Добавить свой ответ
Предмет:
МатематикаАвтор:
анонимОтветов:
Смотреть
помогите англ. 11 класс
6.Choose the correct answer.
1 “I am going to travel by plane.”
He said that he is going / was going to travel by plane.
2 “I’ll pick everyone up and drive them there.”
She said that she will pick / would pick everyone up and drive them there.
3 “I am painting a new piece for the exhibit.”
Mario said he was painting / had been painting a new piece for the exhibit.
4 “I couldn’t read the rest of the book.
She said she couldn’t read / had couldn’t read the rest of the book.
5 “I had eaten all the sweets.”
She said she ate / had eaten all the sweets.
6 “We were driving for hours in the snow.”
They said that they had been driving / drove for hours in the snow
7 Rewrite the first sentence in reported speech.
1 “Where is the TV controller?”
Dad _____________________________________________________.
2 “I will see you tomorrow in class.”
She _____________________________________________________.
3 “Tanya, whose jacket is this?”
He ______________________________________________________.
4 “The phone is ringing.”
She _____________________________________________________.
5 “Do you see your brother often?”
She _____________________________________________________.
6 “We left for New York yesterday.”
They ___________________________________________________
8.Choose the correct answer.
1 Janet told / said / asked that she hated the class.
2 We told / said / asked if it was a long journey.
3 They told / said / asked me the museum was closed.
4 The artist told / said / asked that he used iron to make the statue.
5 Georgia told / said / asked her friends that she would be late
Предмет:
Английский языкАвтор:
vickroschinaОтветов:
Смотреть
помогите пожалуйста английский язык 11 класс
9.Report what the people say using the reporting verbs below.
advise, promise, complain, deny, warn
1 “My house is always a mess,” said Magda.
___________________________________________________.
2 “I will be there tomorrow for sure,” Mike said.
___________________________________________________.
3 “Be there on time if you want to get good seats,” Peter said.
___________________________________________________.
4 “Don’t order the salmon,” said Mandy.
___________________________________________________.
5 “I didn’t take your mobile phone,” said Bob.
___________________________________________________
Предмет:
Английский языкАвтор:
vickroschinaОтветов:
Смотреть
Предмет:
МатематикаАвтор:
анонимОтветов:
Смотреть