## anonymous 4 years ago Evaluate without using a calculator. Answer in radians and degrees. Thank you! (:

1. anonymous

$\sin^{-1} (-1)$

2. anonymous

my answer was 270 degrees, (3 pi/2) however i'm terrible in math so can someone please check my answer? xD thank you.

3. anonymous

$\sin ^{-1}(-1)= \Pi or 180 degrees$

4. anonymous

no it is not right unfortunately because your answer needs to be in the interval $$[-\pi,\pi]$$

5. phi

Are you guys sure?? I always thought sin(-90)= -sin(90)= -1 and -90 is 270

6. anonymous

mistake on my part, should have been $\sin(-\frac{\pi}{2})=-1$ and therefore $\sin^{-1}(-1)=-\frac{\pi}{2}$

7. anonymous

@phi i was wrong it should be -90, or $$-\frac{\pi}{2}$$ not $$-\pi$$

8. phi

@satellite73 - I was getting worried when multiple people were saying pi. btw, the answer could be the interval 0 to 2pi or -pi to +pi , depending on who's asking the question. Personally, 270 and 3pi/2 would be ok with me.