what is the trig identity for negative sin squared

Question

What is the trig identity for negative sin squared

Answer 1

There is also the identity

 

sin²x = [1 - cos(2x)] / 2

 

Then

 

-sin²x = [cos(2x) - 1] / 2

Answer 2

sin²x + cos²x = 1

 

So, sin²x = 1 - cos²x

 

Therefore, -sin²x = cos²x - 1