Hi. There was a question in my math book which I couldn't solve. And I would appreciate if anyone could give me the solution.
The question is about mathematical induction and it's from IB math HL textbook.
Bellow is the question (It's in the picture)
Thanks a a lot
Just one question, how did you get
(k+1)(k+2)/2
from (1+2+...+k+(k+1))
I couldn't follow that part. Could you please explain it a bit?
And thank you for helping me.