00:01
Okay, here we have the location vector of an object, and i can write this.
00:07
I want to as r equals a column vector 2, cosine t, 3, sine t.
00:17
And to work out in v, all i need do is differentiate both items.
00:26
In other words, that will be dr by dt, rate of change of the location.
00:33
Vector and that if i differentiate to cause t i get minus two sine t i differentiate three sine t and we'll get three cosine two so there is v and you want to want to like that is fine or just say x dashed equals minus two sine t y dashed is three cosine.
01:10
Either way is correct.
01:12
That's fine and so is this as a pair of items.
01:19
Now i want to work out v at certain times...