00:01
So here i've written down rolls theorem.
00:02
Let's just review that.
00:04
If we have a continuous function on a closed interval, and the function evaluated at one endpoint a is the same as the function evaluated at the other endpoint b, then rolls theorem says that we have some c value between a and b between the endpoints, where the derivative at that c is zero.
00:25
So before we can use rolls theorem, we just need to check that it's satisfied.
00:29
So first is f continuous on 2 -4? well, that's a check, right? because a quadratic has a parabola as its graph, and that's continuous.
00:43
The next thing we need to check is when we substitute 2 and 4, we get the same output.
00:48
So 2 squared minus 6 times 2 is 12 plus 8.
00:53
Yes, that's 12 minus 12 or 0.
00:58
Well, i guess i shouldn't put a check there because we need to plug in 4.
01:02
Are 4 squared minus 6 times 4 plus 8...