1. Concept forming
The students in the experimental group reflected that it was easy to learn multiplicative identities using the combinatorial teaching materials, and the concept was not easy to forget because they might refer back to the situation.
2. The regular test
In regards to the regular test, the related question about multiplicative identities was 〖(2x−y−4)〗^2= ?. There were 16 questions in the regular test that contained polynomial operation (e.g., 3