00:01
Ok, so let's get started by computing the derivative of our revenue.
00:06
Well, thanks to the quotient rule, we're going to have the rational function with denominator x squared plus 3 squared and the numerator is going to be 3 minus 2x multiplied by x squared plus 3 minus 2x multiplied by 3x minus x squared.
00:29
Perfect.
00:30
Ok, now let me rewrite this guy.
00:33
Well, the denominator is going to be the same, x squared plus 3 squared.
00:39
The numerator is going to be 3x squared plus 9 minus 2x cubed minus 6x minus 6x squared plus 2x cubed.
00:57
Let's simplify.
00:59
We can get rid of this one, this one and this one here.
01:05
Perfect.
01:07
This one and this one.
01:09
Well, the sum of these two guys is going to be negative 3x squared.
01:17
So we are left with negative 3x squared minus 6x plus 9 over x squared plus 3 squared.
01:31
Ok, at this point, let me factorize the numerator.
01:36
This one is going to be negative 3 over x squared plus 3 squared multiplied by.....