00:02
Problem number 21, f of x equals cosine 2x minus x squared plus 2x.
00:17
Now let's plot our function.
00:28
This is our y of y -axis and this is our x -axis.
00:32
Let's name this f of x.
00:53
Okay.
00:55
As we can see, there are two intersection points.
01:01
So good initial points could be negative 1 and 1.
01:08
For our initial point could be negative 1 and 1.
01:21
Okay, the formula for newton's method is x of n plus 1 equals x n minus f of x n over f dash of x n since our f of x equals cosine 2 x minus x squared plus 2 x therefore our f dash of x would be equal to minus 2, sine 2x minus 2x.
02:01
Okay, now we will apply newton's method for the two initial points we've got.
02:08
So let's start with the first one, where x node equals negative 1.
02:15
Let's make a table in order to calculate our iterations.
02:19
X of n, f of x and f dash of x.
02:33
0, negative 1, negative 3 .416145 .8 .1850, negative 0 .41, negative 0 .41289.
02:57
Negative 0 .3, 182805.
03:09
4 .29...