(1)公因式與提公因式

https://www.youtube.com/watch?v=alGXSmefH8A&list=PL37AE43C09FD3EFAD

(2)變號法則與提公因式

https://www.youtube.com/watch?v=caeFDnL2WMs&list=PL37AE43C09FD3EFAD

(3)分組提公因式與因式分解

https://www.youtube.com/watch?v=M6oaelXWafk&index=3&list=PL37AE43C09FD3EFAD

國二上_3-2提出公因式與分組分解

https://www.youtube.com/watch?v=EStx82T2KPY&list=PL37AE43C09FD3EFAD&index=4