00:01
So in this question, in part a, they said evaluate the integral from zero to infinity of 29 x to the n, e to the negative x dx, for n equal to zero, one, two, and three.
00:17
And in part b, they said guess the value of the integral from zero to infinity of x to the n times e to the negative x d x, where n is an arbitrary positive integer.
00:28
And since it appears that you already have b correct, you've actually done all of the work necessary for a already.
00:39
For example, if n is 0, we have the integral from 0 to infinity of 29 times x to the 0 power, times e to the negative x d x.
00:56
Now the 29 constant multiple, slide that to through the integral sign.
01:02
You've got 29 times the integral from 0 to infinity of x to the 0 times e to the negative x d x.
01:12
But according to be, this interval is equal to 0 factorial.
01:19
So you have 29 times 0 factorial.
01:23
Zero factorial is 1.
01:27
So 29 times 1 is 29.
01:31
It has 29.
01:32
It has 29.
01:32
It has 2.
01:32
How about if n is 1? well, if n is 1, we have the integral from 0 to infinity of 29 x to the 1st power times e to the negative x d x.
01:47
Again, 29 is a constant multiple...