## Trending News

### 1 Answer

Relevance

- KateLv 61 decade agoFavorite Answer
sin(-22.5)

=-sin(22.5)

Using the half-angle identity

sin^2(22.5) = (1-cos(45))/2 = (1-(1/sqrt(2)))/2 = (sqrt(2)-1)/2sqrt(2)

= (2-sqrt(2))/4

=> sin(-22.5) = -(1/2)sqrt(2-sqrt(2))

- Login to reply the answers

Still have questions? Get your answers by asking now.