0:00
All right.
00:01
So let's say we have a vector a that points in the negative x direction like this and has a magnitude of 22.
00:10
So a is like this.
00:13
And then a vector b points in the positive y direction.
00:18
And it has some magnitude, which we're not told.
00:22
But we're told find the magnitude of b if a plus b has a magnitude of 37.
00:27
So basically what we'll have is 30.
00:31
27 squared should equal 22 squared plus the magnitude of b squared in pythagorean theorem.
00:38
So if you do 37 squared minus 22 squared and then take the square root, that tells us b has, let's write this.
00:47
This is part a.
00:48
B has a magnitude of 29 .75 units.
00:54
And we want to sketch a and b.
00:57
We've kind of already done that.
00:59
Let's go to the next question.
01:03
It says, given the vectors a is 2 i -hat plus 6 j -hat, and the vector b is 3 -i -hat minus 2 j -hat.
01:18
We want to draw the sum of these two.
01:21
So c is just going to be 5 i -hat plus 4 j -hat.
01:27
So if you graph that kind of crudely, we go over five up four...