I am in over my head, knowing very little about CL. But. My students are learning to write intervals of increase/decrease or positive/negative values for polynomial functions, and I am building a Desmos activity that will check their answers. When the answer is a single interval, such as (-3,-1), I have no problem. On a math input screen, I used

correct = input1.submitted and input1.latex = “\left(-3,-1\right)”
correct: correct

and answers checked perfectly. But a problem occurs when I need a union of two or more intervals, such as (-3,-1)U(5,6). I tried using

correct = input7.submitted and input7.latex = “\left(0,1\right)\bigcup\left(5,6\right)”
correct: correct

and having students just cut and paste a U symbol that I provided in the activity. It didn’t check correctly. I also tried \cup. Then I tried to insert the word or as follows

correct = input7.submitted and input7.latex = “\left(0,1\right)or\left(5,6\right)”
correct: correct

but it was recognized as latex (?) and when students enter a space before and after the word, it doesn’t check correctly.

How can I get the pasted U symbol to check correctly? I want students to enter answers in the format (-3,-1)U(5,6). Thanks for helping a newbie!

I ran into this issue with non-linear inequalities, and I ended up using multiple choice for this. The code is a little heavy, but you should be able to adapt it using the hide answers table.

Thank you! I actually viewed your activity earlier today while searching for answers. I love the idea of using buttons and will have to try adapting the CL.

SteinSchreiber
I copied your Interval Notation button screen and tried to adapt it to solve the quadratic:
-(x+3)(x+8)≥0. The “correct” message never pops up but the show correctness button at the top does show students when they do and do not have correct answers. I tried to change the code but it was way over my head. Any suggestions?

On the second screen you will have to change the hiddenAnswers component to the following:
a -8
b -3
multipleChoice 1
c (type any number)
d (type any number)
Inequality: -(x+3)(x+8)>=0
Union 0

Note the values for c and d don’t matter since for your inequality a union isn’t necessary.
It will show a next to
Your Interval Notation Answer:

But the Correct won’t necessarily show up on the graph clearly. You would have to Edit the Graph and change Line 33 to something that would work for you. (I attached a picture of Line 33, you would probably have to change the Center (0,-1) and divide the width and height by 2.