This isn’t exactly a CL question, but I didn’t have any luck on the Desmos Facebook group.
I am wanting students to be able to graph a piecewise function by “plotting points,” then clicking an action button to check their work. If their points are in the right place the button causes an animated “connect the dots.” I have the CL working for the graph animation, but I am stuck on getting the point to be both open and have vertical drag. Is it not possible? And if not, any ideas for a workaround? (The points are currently “layered” from left to right.)
The reply you got from Elayna MG was correct: create your draggable point as normal, then create a non-draggable point with the same coordinates. For example, P=(2,a) to create your vertically draggable point and then P_1=P to create a point you can stylise however you want - open circle, change the size, etc.
Once done, if you reduce the opacity of the draggable point to 0, it is invisible but still movable - so it ‘feels’ like you’re moving the open circle.
Hi, the activity that is posted does not seem to be the activity you described. Do you happen to have the activity? This seems amazing if you got it to work, as I am trying to get students practice with one piece piecewise functions.
I made this a couple weeks ago (screen 1) as a template. Maybe that will be of use? You can change the function definitions in the CL. Click on the number above the point to switch between open and closed dots.
I apologize. As I was unable to create what was in my head, so I went a different direction and replaced screen 3 with something else. I probably should have started a new activity instead. Apologies for the confusion. See Daniel_W’s comment, that seems to be helpful.
Wow! This is amazing, thank you so much! I will attempt to modify it and will post an update if I’m able to do it. My students were working on 2 and 3 piece piecewise functions on Delta Math, but they are still so confused, so it would be great to be able to give them more immediate feedback with just one piece! Thanks so much. If I can’t do it I’ll just have them graph the open and closed circles by hand and will use Desmos’s teacher dashboard to monitor.
That would be amazing if possible but okay if not. I’m looking at it now but it is a lot (on slide 2 of this is how far I got: 12.4 • Activity Builder by Desmos I just tried making the 2nd 2 functions invisible by using open dots and the same starting and ending point, but I don’t think it worked).
I am working on an alternate template using 2 movable points and a line that goes through them (on slide 1 above). However, your template is so cool because the kids also get to practice slope with more detail, seeing each step of the slope (which is another thing the students are confused about). I will see if I can get that to work and will post it here if so.
However I would be looking for something such as: f(x)= - 2x+3 for -1 <=x< 2
(that would be the problem itself: just one piece of the function).
Or, another example of another problem would be something like: f(x)=-2x+3 for x<2
Give this a try and let me know if it works for you. You can set the values in the CL of the graph and then you just have to make sure the bounds of the graph include all of the points in the domain. I made 3 examples but they all use the same template. [Copy of] 12.4 • Activity Builder by Desmos
My students’ understanding of piecewise linear functions greatly advanced this week by letting them practice one-piece piecewise linear functions. Here is how I used Mr. Wekselgreene’s work just in case anyone else wants to have a ready-to-go activity:
Below has an example of a non-linear one-piece piecewise linear function on slide 1:
Below we just practiced one-piece piecewise linear functions where y= a number:
Here we will do piecewise functions using y=mx+b (without substitution). Here is also an example of a “fill in the blank” graph with editable labels that are checked:
Writing the equation for one-piece linear piecewise functions:
It was amazing to see them learn and grow. They are still stuck on which way to apply the slope once they’ve gotten the point, so in the future I may just give them a point and just have them focus on the graphing piece. This is the best tool.
