Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
DDT
Group Title
Find minimum of : \sum_{k=1}^{n}a_{k}^{2}+\left(\sum_{k=1}^n a_k\right)^2. My teacher told me that I shoul use CauchySchwarz inequality. Any tips?
 one year ago
 one year ago
DDT Group Title
Find minimum of : \sum_{k=1}^{n}a_{k}^{2}+\left(\sum_{k=1}^n a_k\right)^2. My teacher told me that I shoul use CauchySchwarz inequality. Any tips?
 one year ago
 one year ago

This Question is Closed

henpen Group TitleBest ResponseYou've already chosen the best response.0
\[ \sum_{k=1}^{n}a_{k}^{2}+\left(\sum_{k=1}^n a_k\right)^2\] \[\left(\sum_{k=1}^n a\right)^2=\sum_{k=1}^n a^3\] So your question boils down to \[\sum_{k=1}^n a^2+ a^3=\sum_{k=1}^n a^2(a+1)\]
 one year ago

henpen Group TitleBest ResponseYou've already chosen the best response.0
http://users.tru.eastlink.ca/~brsears/math/oldprob.htm#s32
 one year ago

henpen Group TitleBest ResponseYou've already chosen the best response.0
The link is the ()^2=(^3) proof
 one year ago

henpen Group TitleBest ResponseYou've already chosen the best response.0
Although that's not Cauchy Schwartz.
 one year ago

DDT Group TitleBest ResponseYou've already chosen the best response.0
I didn't realise that task has another assumption :\[\sum_{k=1}^{n}p_ka_k=1\]
 one year ago

henpen Group TitleBest ResponseYou've already chosen the best response.0
Sorry, I forgot that a1 does not necessarily equal 1, a2=2 etc. forget what I've told you so far.
 one year ago

henpen Group TitleBest ResponseYou've already chosen the best response.0
http://en.wikipedia.org/wiki/Cauchy%E2%80%93Schwarz_inequality#Statement_of_the_inequality you want the final formula of this section
 one year ago

henpen Group TitleBest ResponseYou've already chosen the best response.0
Or do you think a1=1, a2=2 etc in this problem?
 one year ago
See more questions >>>
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.