Предмет: Алгебра, автор: китсан

доказать тождество sin5a-sin3a/2cos4a=sina

Ответы

Автор ответа: мариченька

sin5a - sin3a/2cos4a=(2sin((5a-3a)/2)*cos((5a+3a)/2)) / 2cos4a = 2sin a*cos4a/2cos4a= sin a

Интересные вопросы

Предмет: Английский язык, автор: 11348555555555

Tasks for the summative assessment for the term 1 (grade б) reading read the text and do tasks meals in britain traditionally english people have three meals a day: breakfast, lunch and dinner. breakfast is served in the morning. it used to be a large meal with cereal, eggs and bacon, sausages, tomatoes. but such a large breakfast takes a long time to prepare and is not very healthy nowadays, britain's most popular breakfast consists of cereal, toast with marmalade. juice and yogurt with a cup of tea or coffee lunch is a light meal. most people have no time to go back home for lunch so they eat at school, cafes, pubs or restaurants. the main meal is dinner, which is usually between 6 and 7 p.m. a typical evening meal is a meat dish with vegetables and dessert the most important meal of the week is the sunday dinner, which is usually eaten at l p.m. the traditional sunday dish used to be roast beef, but nowadays pork, chicken or lamb are more common on sunday evenings people have supper or high tea the famous british afternoon tea is becoming rare, except at weekends. tasks questions 1. how many meals a day do english people have? 2. what did they use to eat for breakfast nowadays ? true false 3. nowadays the most popular britain's breakfast consists of milk, bread and chocolate 4. lunch is large meal 5. english people eat lunch at school, cafes , pubs or restaurants 6.in the morning english people have supper score б writing choose one topic below and write7sentences about i
даю 30 балов

6 лет назад

Предмет: Английский язык, автор: pasha1234516

Вот продолжение больше там ничего нет

6 лет назад

Предмет: Геометрия, автор: Аноним

соч по географии за 1 четверть 7

6 лет назад

Предмет: Математика, автор: Волчонок1999

ПОМОГИТЕ СРОЧНО ОЧЕНЬ ПРОШУ

найдите площадь прямоугольника, ширина которого 3 1/5 дм и она меньше длины на 1/4 дм

10 лет назад

Предмет: Физика, автор: lalul

пользуясь таблицей плотностей определите массу а)оловянного бруска объемом 2 м3 б)гранитной глыбы объемом 8 см3 в)парафиновой свечи обемом 8 см3 г)фрагмента бетонной стены обемом 20м3 д)дубовой балки объемом 0,8 м3

10 лет назад