
Please Help me
So I was trying to solve this problem arcsin(sin(3pi/5)
and so far I got that the arcsin(sin) can't cancel because the 3pi/5 is out the range of pi/2<x<pi/2
So I looked for the reference angle...
and I know that 3pi/5 will lay on QIII because is going clockwise.
So I looked at the theta hat, and I see that theta hat is 2pi/5..
Is this right... or do I have a mistake... please help. I kind it feel that I did something wrong. (Hi)

Re: Please Help me
I would use the following:
$\displaystyle \sin(x)=\sin(x)$
$\displaystyle \sin^{1}(x)=\sin^{1}(x)$
$\displaystyle \sin(\pix)=\sin(x)$
to obtain:
$\displaystyle \sin^{1}\left(\sin\left(\frac{3\pi}{5} \right) \right)=\sin^{1}\left(\sin\left(\frac{2\pi}{5} \right) \right)=\frac{2\pi}{5}$

Re: Please Help me
Also keep in mind that arcsine does not just have to be 90 degrees  90 degrees, but can also be other sets of domains

Re: Please Help me