In my code I wrote :

 $\therefore$ There is a total of 21,168 ways that we can choose 2 chemists and 3 physicists. 

However, I am getting the undefined control sequence error. I have used packages amsfonts and amsmath, but that doesn't seem to fix the problem.

Thank you.


You need to load amssymb:





enter image description here

Not the answer you're looking for? Browse other questions tagged or ask your own question.