00:01
So we want to find the first time, the smallest time, where this function is equal to 20.
00:13
And we want the exact value.
00:15
So we know we divide by 40, and we get one -half.
00:26
And we know there are two angles using the unit circle where the sign is equal to one -half.
00:35
And that one is pi over six, and that one is five -five -over -six.
00:39
So we get pi over six and five pi over six plus two pi n.
00:56
Then we'd be adding four pi and let's see what we get with those.
01:07
So we have a hundred pi t is equal to and four pi is going to end up being 24 pi over six plus pi over six so that's going to take us up to 25 pi over six plus two pi n and then 4 pi again is that 24 pi over 6 plus 5 pi over 6 and that's going to take us to 29 pi over 6 plus 2 pi n and now we need to do our division or our multiplication by 1 over 100 pi and we need to do that to all of these as well 1 over 100 pi everything by that and so that gives us a t value of distributing here that's going to end up being a 4 in the bottom.
02:06
So that's going to end up being 25, which cancels out that 100, and that becomes a 4 on the bottom.
02:11
So we have pi over 24.
02:17
Excuse me, that's going to end up being 1 over 24.
02:21
Let's erase that.
02:23
Because again, if i multiply this by 1 over 100 pi, the pies will cancel...