00:01
To solve this problem, it's easiest to first start from the inside and work outwards.
00:08
So at first, we're going to try to find the length or the output of sign of 11 pi over 6.
00:17
And we know that from the unit circle, that if we go once around the unit circle, we get back to the same point.
00:24
In other words, this is saying, if you have the sign of some angle theta and you add or subtract 2 pi radiance, get back the sign of theta.
00:37
We can use this to get 11 pi over 6 in terms of a smaller angle to which we can figure out the sign.
00:48
So if we subtract 2 pi radiance from 11 pi over 6 and simplify it, we get that the sign of 11 pi over 6 minus 12 pi over 6, we did this to get a common denominator will just be the sign of negative pi over 6.
01:14
And here you can either use the unit circle or, if you memorize it, you can use the unit circle, or you can use the fact that the sign function is odd.
01:30
And by that, i mean say, pi over 6 might be right here and pi over 6 will be over here.
01:36
And we see that the sign of pi over six is negative sign of negative pi over six.
01:43
In other words, the sign of negative pi over six will be negative sign of pi over six.
01:54
And now, if you know the sign of pi over six, you can plug it in, but at first it might be easiest to actually solve for it...