Сколько корней имеет уравнение cosx*cos4x-cos5x=0 на промежутке [0;п]

1.Math the words with their definions.

1)FA Cup                         a)To produce or desing something that has not existed befor.

2)A set(of  something)  b)Of the present time.

3)A stadium                     c)A large sports ground surrounded by rows of seats.

4)To invent                       d)An English football competition that takes place every year.

5) To introbuce                e) A group of similar things that belong together in some way.

6)Proper                            f)To be the starts of  something new.

7)Modern                           g)According to the rules.

2.Read the text and wtite the answers to the questions.

      Football is the most popular sport in Britain,particularly amongst men.It is played by boys in most schools.Most towns have an amateur football team.Football is also the most popular spectator sports in Britain.The rules of football are relatively simple:two teams of 11 players try to get a round ball into the opposing team's goal and to prevent their opponents from scoring. The ball may be kicked or headed,but never handled.except by the goalkeeper.The football Association was founded in 1863 to decide the rules of football and the resulting game became known formally as association football.It is something also called soccer.Many of today's leading clubs were established shortly afterwards.

1)Is footballmore popular with men or women?

2)What is non-professional football team called?

3)How many teams are there in the game of football?

4)How many players are there in each of the teams?

5)What are players trying to do during the game?

6)Who can take the ball with the hands during the game?

7)When was the Football Association founded?What was the result of it?

8)What is another name for football?

две окружности равных радиусов с центрами в точках О и О1 пересекаются в точках А и В . Одна сторона треугольника АОО1 равна 13см ,другая 6см . Определите расстояние между центрами окружностей