00:01
For this problem, we're asked to sketch the path r of t equals 1 minus t squared 1 minus t for t between negative 2 and positive 2, indicating the direction of motion.
00:08
We're then asked to draw the velocity and acceleration vectors at t equals 0 and t equals 1.
00:13
So we can take a few sample points.
00:15
For instance, r of negative 2.
00:17
You can see it would be equal to 1 minus negative 2 squared, so that would be 1 minus 4, or negative 3 in the x component.
00:24
And then 1 minus negative 2, so 1 plus 2, so that would be 3 in the y component.
00:30
Then at negative 1, we have 1 minus negative 1 squared.
00:35
So we'd have 0 in the x component.
00:37
1 minus negative 1 gives us 2 in the y component.
00:40
R of 0 clearly gives us the point 1 1.
00:45
R of 1 would then be equal to 1 minus 1 squared.
00:49
So again, 0 in the x component, and then 1 minus 1 or 0 in the y component.
00:54
And then at r of 2, we'd have 1 minus negative 2 squared.
00:59
So that gives us negative 3 in the x again but then we'd have 1 minus 2 in the y component so that would give us negative 1 so we can then create a rough little sketch here so we know that we start at the point negative 3 positive 3 so that would be over here then we go to x equals 0 y equals 2 then we go to x equals 1 y equals 1 then we go to the point 0 oops actually i missed it that's the point we want we go to 0 0 and then we go to negative 3 negative 1 so we'd have that our path is something like this then we're asked to well draw the velocity and acceleration vectors at t equals 0 and t equals 1 what we can do here is find the derivative of r we we have r prime of t will be equal to negative 2 t, negative 1...