00:01
Here the model given is xt is equal to 2t plus xt minus 1 plus wt, where x naught equal to 0 and wt represents the gaussian white noise with variance sigma w square.
00:22
So, we have to prove that del xt is equal to 2t plus wt, where del denotes the first difference and del square denotes the second difference etc.
00:33
It goes on.
00:34
So, now, we have to find a del xt that is the first difference.
00:39
So, we know that del xt is equal to xt minus xt minus 1.
00:44
So, by substituting the given model we can have xt is equal to 2t plus xt minus 1 plus wt minus xt minus 1.
00:55
So, we can cancel these two which is equal to 2t plus wt.
01:00
Then second step is we have to find del square xt.
01:04
So, now, we have to take that a second difference that is del of del xt which is equal to del xt minus del xt minus 1 which is equal to 2t plus wt minus 2 times t minus 1 plus wt minus 1 which is equal to 2t plus wt minus 2t plus 2 plus wt minus 1...