Question

Write the value of

`1 - 2 \cos {}^(2) c`


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Answer 1

Explanation:

1-2cos²c.

> (cos²c+sin²c)-2cos²c. (cos²c+sin²c=1)

> cos²c+sin²c-2cos²c

> sin²c-cos²c.

is your correct answer.

hope this helps you.