Evaluate without using a calculator. Answer in radians and degrees. Thank you! (:

Question

anonymous · Answer

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

anonymous · Answer

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

anonymous · Answer

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

anonymous · Answer

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

phi · Answer

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

anonymous · Answer

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

anonymous · Answer

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

phi · Answer

@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.