00:01
All right, so looking through the work that you have here, you got a lot of really good information into here.
00:05
The first thing we see is we know that sine of 2x is 2 sine of x, cosine of x.
00:10
So i'm going to move this over first.
00:11
So the square root of 2 times cosine of x minus sine of 2x is equal to 0.
00:17
And now i'm going to convert that.
00:19
So the square to 2 of cosine of x minus 2 sine of x cosine of x is equal to 0.
00:26
So then just as you did, i'm going to go ahead and factor out that cosine.
00:30
This is going to become cosine of x over here, and then i have a square root of two minus two sine of x is equal to zero.
00:38
Now, from here, we're going to set these two pieces equal to zero.
00:41
It's kind of like factoring.
00:43
So the first thing we have here is cosine of x as equal to zero.
00:47
Well, just like you said, this happens at pi over two, and it happens at three pi over two...