00:01
Okay, we're going to consider first graphing our vector value function r of t that's given.
00:07
Now, notice between the cosine and sine in our i and j component, that is, if it didn't have a k piece, that would just be a circle of radius 2 centered right on zero zero.
00:19
Because we have a k piece, now as we draw that circle, we actually raise in height.
00:24
So you can think of it like a slinky as it goes up.
00:28
Okay, so that's a pretty good representation of our function.
00:40
So now in a, it's asking us to insert a negative 1.
00:46
Now, notice that negative 1 is inside the parentheses.
00:50
So really, that's like a 2 cosine t minus 2.
00:55
So because of that minus 2 in the x direction, what would happen is you really could just take your shape and move it back to in the x direction.
01:07
And so now instead of being centered, and remember, it had a radius of 2.
01:12
And so now it'd be centered actually at negative 2.
01:16
I'm going to put it back for our next problem.
01:20
Okay, so we'll just make a comment on that, move 2 in the negative x direction...