00:01
I was shifting away from just the average rate of change, we're going to start looking at the tangent line.
00:07
So before we had an example, or for example, we had a function x squared, some parabola, and we were looking at the average rate of change by drawing a secant line from this point to this point, and then calculating the slope.
00:20
Well, now no longer, we actually want to look at the tangent line and the slope of the tangent line.
00:27
This is directly leading us into what the derivative is because the derivative takes these siquant lines and brings them closer and closer together until what we have is a tangent line to the graph.
00:43
So if we draw tangent lines at the different points, we want to estimate their slopes.
00:50
So estimating their slopes, we end up seeing that, for example, if we want to estimate the slope of the tangent line here, we see it would be zero.
00:59
The best way to estimate the slope of a tangent line, in my opinion, would be to look closely at the graph and draw this tangent line.
01:08
The closer we zoom into a function, the more we realize it is a line.
01:12
It's called local linearity.
01:15
So if we look at this now, we see that close to this point, this is at 0 .6, i chose this arbitrarily.
01:23
We see that it rises about one and runs one.
01:26
So the slope is about one, but it's going to be slightly more than one, slightly steeper slope than one.
01:34
So that's how we interpret this, and then we could even look closer at the value of one and see that at this point, we have a slope of two.
01:42
That is the given slope that we have, which makes sense as we learn more about the derivative...