As I work on writing posts about my previous Desmos activities I wanted to start with this one here on Domain & Range. I had been looking for an adaptation to the domain & range finder that we made by hand. I was unsure of how to use Desmos to create this until I saw Mr. Polak’s (if anyone knows his handle or a link I would love to give more credit) own domain & range activity on Desmos.
With his idea of using inequalities to make boxes I was able to make my own adjustments. In this activity, students start with examples of the correct domain and range displayed as a rectangle over the graph. Students then get to use the sliders to adjust the boxes. The goal of this is to help students visual domain and range and not get overwhelmed with numbers and inequalities. This was designed with remedial students in mind, but should work well for all students. After students understand the concept of domain and range they get to type in the inequalities and watch the rectangles change.
My students struggled at first with seeing how to drag the points to change the size of the rectangle. I would suggest modeling this with your students. Some of my students also struggled with how to write the inequalities so it might be helpful to review that as well or create a mini activity on that for your students.
As always I love any feedback that people have to offer and hope to continue to improve on the activities.