00:01
So here in this question, we're going to evaluate by using integration.
00:07
So we're supposed to do this question.
00:09
We were supposed to find an expression on giving the enrollment to t years from now and also the enrollment five years from now.
00:16
So this is the expression given here.
00:18
So i can write this as this is a variable n which is dependent on t or time where n is the number of students enrolled.
00:30
So i can write it like this 1 plus 0 .2t raised to minus 3 by 2.
00:37
I just changed 10 dash t to d n by d.
00:39
Nothing else.
00:40
So here what i'm going to tell you is that we'll be doing integration by substitution.
00:44
So we're going to substitute this particular term as you.
00:48
So then what would happen is 1 plus 0 .2 can be written as u.
00:52
So by differentiating this term, we'll be getting 0 .2 d t.
00:57
This would be 0 because that's a constant is equal to d u.
01:00
So instead of t, i'd be substituting this whole term with u.
01:06
So d n by d would be coming.
01:08
So before that i'll just show you that i'm going to rearrange this particular expression by taking dn on one side and d t on the other side.
01:14
So then this would become d n is equal to 2001 plus 0 .2t raised to minus 3 by 2 d t so this would be the expression.
01:26
Now we would be replacing this particular t we have d t we have to d u so what would happen is d t would be nothing but d u by 0 .2 so this would be the change so instead of d t i could use d u by 0 .2 so then the changed thing would happen here i just write it down so then i can write d n is equal to 2 000 instead of 1 plus 0 .2t i can write it as u u raised to minus 3 by 2 instead of d t i can write d d u by 0 .2, du by 0 .2.
02:04
So i can cancel this thing and this thing that would give us 10 ,000.
02:08
So then i can write d n is equal to 10 ,000 u raised to minus 3 by 2, du.
02:18
Yeah, du...