00:01
We have been given a function, and first we have been asked to determine the local extrema.
00:06
Then we will determine regions of concavity, and finally, we will look at inflection points.
00:14
For the extrema, let's first find the derivative.
00:19
Our derivative is 6x squared minus 12x plus 6.
00:26
We would have extrema or potential extrema, that is critical numbers, where the derivative is zero, or where the function's non -differentiable.
00:36
The function's never non -differentiable, though, since it was a polynomial.
00:41
So let's set the derivative equal to zero and see where that's true.
00:47
I can factor out a six, which would give me six times quantity x squared minus two x plus one.
01:00
And that will factor to x minus 1 times x minus 1.
01:08
Solution then, and it's the only single critical number, is that x equals 1.
01:14
If we check on both sides of that to see what sign we have for the derivative, we would see that if we fill in 0, we will get a derivative that is positive, and if we fill in a number like two, we would get an answer that is still positive.
01:40
So there's no change in direction.
01:43
This is increasing on both sides...