Online Course Discussion Forum

AMC10 MC II-A Algebra Lesson 9

 
 
WuZeyin的头像
AMC10 MC II-A Algebra Lesson 9
WuZeyin - 2022年07月17日 Sunday 07:03
 

I don't quite understand practice question 9.18, to be specific the sigma notation. I need some help with that. Thanks!