00:01
I've already drawn the diagram.
00:04
The resultant is 3 kiloons directed along the positive x -axis.
00:13
So i need to figure out f sub b and 0.
00:17
Well, f sub b and f sub a are going to cancel each other out in the y direction.
00:25
So in the y direction, we would have f -a, sine 30 minus fb sine theta and they're going to equal zero.
00:46
In the x direction we're going to have f a cosine 30 plus f b because they're in the same direction um cosine theta and together they're going to equal 3 kilonauts.
01:12
So i need to figure out f sub b and theta, trying to think about whether there's a way to do this other than graphing.
01:26
And i imagine we could do this using some trig identities.
01:37
But in the end, it's going to be a lot easier just to graph it.
01:41
So i'm going to go ahead and graph it.
01:43
F .a.
01:44
Is 2.
01:45
Sine 30 minus fb.
01:49
I don't know, so i'm going to call that y, sine x equals zero.
01:57
And now, two cosine 30 minus y cosine x equals three.
02:15
Oh, i didn't put an equal sign in there.
02:17
That's my problem there we go okay so um theta and f sub b so let's scroll in here i'm thinking that f sub b because i put in two and three it's probably no more than five for sure so i'm going to set my y axis from zero to five now on the axis.
03:01
It's definitely not more than 90 degrees, so i'm just going to set it from zero to 90.
03:10
Okay.
03:12
Why don't i see the blue one? there's the blue one.
03:18
That answer is not reasonable.
03:21
The answer that i'm getting is like 140 degrees, but that doesn't make sense.
03:32
140 degrees...
