Main Ideas

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Here are the main points that are addressed in the video. Please read these and think about them as you watch.

Speed requires movement, so at a particular instant in time a moving object doesn’t have speed
We can approximate an instantaneous speed with an average speed over an interval of time immediately before or after the moment in time
The average speed is either an over-estimate or an under-estimate of the instantaneous speed
If we compute both an over-estimate and an under-estimate, we can compute how much error there might be in our approximation