Предмет: Алгебра, автор: pochemunikita

cos2x= - корень 3/2
хелп

Ответы

Автор ответа: Guest305
0

Ответ:x=±π÷6 + π*k(или n),k(n)∈z

Объяснение:cos2x=±arccos(-√3÷2)+2πk(n),k(n)∈z

2x=±π-arccos√3÷2 +2πk(n),k(n)∈z(Делишь обе части на )

x=±π÷2 - 5π÷6 + 2π÷2 *k(n),k(n)∈z

x=± π÷6 + πk(n),k(n)∈z

(где деление там дробь; ставьте k,если вы так пишете, могут писать n)

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The track is one of the basic features of a railway. It is also called the permanent way. The fact is that in the early days of railroad building the workers first had to lay temporary tracks to transport the materials to the construction site.
And only after that they laid down the permanent tracks on the permanent way, as it was called. The permanent way consists of rails, ties and ballast.
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The ties on most tracks were almost all of wood and in order to make them last longer they were treated with creosote. The ties are not laid upon the earth for the earth cannot support the track structure. They rest upon a bed of crushed rock, or gravel, which is called ballast. Ballast supports the track structure, holds the track in position and provides needed drainage.
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