00:01
In this question, we are asked to find the radius of convergence of the following series.
00:06
To do that, we are going to use the ratio test.
00:12
By the ratio test, we first need to find the limit of the absolute value of a .n plus 1 over a .m.
00:21
Where a .n is a general term of our series.
00:26
So in our case, this is going to be limit of the absolute values.
00:30
Now we are going to replace n by n plus 1 everywhere.
00:34
We are going to get n plus 1 factorial.
00:36
Times x to the n plus 1xx 1x 3 times 5 and now this product will be all the way to n plus 1 to 2 n plus 1 now we need to multiply this by the reciprocal of a n because when we divide 2 fractions we keep the 1 fraction and multiply by the reciprocal of the fraction in the denominator we are going to get 1 times 3 times so on times 2 n minus 1 divided by by n factorial times x to the n.
01:21
This is equal to the limit of the absolute value.
01:26
Now n plus 1 factorial over n plus n factorial is equal to n plus 1...