Предмет: Алгебра, автор: lediKassa

Вычислить соs2a, если sina= -3/5

Ответы

Автор ответа: hovsep50

0

cos2a = cos²a - sin²a = 1 - 2sin²a = 1 - 2·(-3/5)² = 1 - 18/25 = 7/25

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Summative Assessment for the units «Reading for pleasure», «Entertainment and media» (7 grade)

Name: _______________________________Grade: _________

Assessment criteria:

1. Understand some specific information and detail in short, simple texts on a growing range of general and some curricular topics;

2. Understand an increasing range of short supported questions on general and some curricular topics;

I. Reading:

Read the text

Sherlock Holmes - The Sign of Four

For many years, I shared an apartment in London with my friend, Sherlock Holmes.

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Sherlock Holmes did not care if his clients were rich or poor. He enjoyed solving their interesting problems. He was very happy when he was working. It was the most important thing in his life.

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