00:01
I want to find the first four nines row terms.
00:04
This is the chlorine series for this function, and then proceed to find the power series, and its interval of convergence.
00:14
So first we know that ln of 1 plus x is equal to x, x squared over 2, plus x cubed over 3, minus x to the 4th over 4.
00:28
So then ln of 1 plus 4x is equal to 4x minus 4x squared, over 2 plus 4x cubed over 3 minus 4x to the 4th over 4th.
00:50
Okay, so from here, that means that this is going to be the summation of k equals 0 to infinity, negative 1 to the k, 4x to k plus 1 over k plus 1 factorial.
01:17
To find where it converges, let's take the ratio test.
01:19
As an approach is infinity, negative 1 to the n over 4x to the n plus 1...