A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 4 years ago
Sum of first n triangle numbers
anonymous
 4 years ago
Sum of first n triangle numbers

This Question is Closed

cwrw238
 4 years ago
Best ResponseYou've already chosen the best response.01,3,6,10.. is this the series?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0yeah, the one generated by n(n+1)/2

cwrw238
 4 years ago
Best ResponseYou've already chosen the best response.0right  i remember that now but i don't recall the sum formula

cwrw238
 4 years ago
Best ResponseYou've already chosen the best response.0i can only suggest googling it

UnkleRhaukus
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1345110210994:dw

cwrw238
 4 years ago
Best ResponseYou've already chosen the best response.0@UnkleRhaukus  good drawing

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Yeah, but that's only proving what we get, not how to get there

cwrw238
 4 years ago
Best ResponseYou've already chosen the best response.0yes  i see what you mean  it seems that its a guess, which is then proved by induction

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0\[S_n=\Sigma \frac{n(n+1)}{2} = \frac{1}{2} \Sigma (n^2+n) = \frac{1}{2}(\frac{n(n+1)(2n+1)}{6}+\frac{n(n+1)}{2})\] \[ =\frac{1}{12}(n(n+1)(2n+1)+3n(n+1)) = \frac{1}{12} (n(n+1)(2n+1+3)) \] \[= \frac{1}{12}(n(n+1)(2n+4)) =\frac{2}{12}(n(n+1)(n+2)) = \frac{n(n+1)(n+2)}{6}\]

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0How did you get the sum of n^2?
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.