I want to show a text note based on a student having moved a point in a graph

Questions
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1

I’ve been using this activity for years but just added screen 2.

Related Rates

I’m really just trying to avoid having too much of a “wall of text” all at once that students won’t read, so want to have 3 phases to the screen.

First they press the button for the “example” which shows the graph and they are instructed to move the point to adjust the radius. That works fine.

Then once they actually interact with the point, the last blurb of text will appear. That also works fine, HOWEVER as they slide the slider, if they go back over the starting point x=3, the blurb briefly disappears. This is because the only way I’ve figured out to make the blurb appear AFTER they interact with the graph is to put a variable in the graph:

  • m_{oved}={s=3:0,1}

and then the blurb is hidden when this =0. What I really want is to somehow record the FIRST movement of the point and then make the blurb visible from that point forward, so it doesn’t disappear if the student moves the slider back over the starting point.

2

What you want is a way of handling State Management in the calculator - something it doesn’t know how to do well. Try using a ticker with this:

m_{oved}\to\left{\left|s-3\right|>0:1,m_{oved}\right}

What it does:

  • checks if m_{oved} is at all different from a value of 3
  • if it is different from 3 make m_[oved} equal to 1
  • if it isn’t different from 3 just keep it as it was

This will cause the calculator to ‘remember’ the state. I’ve added that and make a couple quality of life improvements here: [Copy of] M140 Sec. 4.1 Pre-Class: Related Rates • Activity by Mike Gleeson

3

Similar shares to @Mike_Gleeson’s also using tickers from two of our Graph Specialists! One in a geometry graph and another using your base graph. Regarding the first it is difficult to tell if the ticker is running, and more so to stop it. It may improve performance, but the tradeoff is the visibility you have in @Mike_Gleeson’s and the second graph.

If you ever notice it’s not working, check that the ticker is running. If it’s paused, it won’t work.