Question

1-cos2x / 1+cos2x = tg²x Докажите тождество

Answer 1

1) 1-cos2x=2sin²x

 

 1+cos2x=2cos²x  

 

2) 2sin²x/2cos²x = tg²x 

 

tg²x = tg²x 

 

Чтд.

Answer 2

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