A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 3 years ago
prove that x²+2xy+3y²≥0 for all x, y E R
anonymous
 3 years ago
prove that x²+2xy+3y²≥0 for all x, y E R

This Question is Closed

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1hint: Expand \((x+y)^2\)

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0i'm sorry i'm still lost

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1what can you say about the number \((x+y)^2\)? can it ever be negative?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0well i thought anything squared would be true bit i can't get the two brackets the same as i can't get 3y squared

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1try and first expand \((x+y)^2\) and then see what else you need to add to this in order to get your original expression of \(x^2+2xy+3y^2\)

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0so the answere would be (x+y)^2 + y^2

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1not quite  what do you get when you expand \((x+y)^2\) ?

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1correct  now what do you need to add to this in order to get to your original expression?

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1so we end up with:\[x^2+2xy+3y^2=(x+y)^2+2y^2\]now  can you see that this can never be negative?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0ok thanks while i have you i have to do this using the same axsis and scales graph the functions f(x)=x and g(x)= 2x  3

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1yw :) could you please post that as a separate question. thanks.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0using the same axsis and scales graph the functions f(x)=x and g(x)= 2x  3

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1< I meant post in the list to the left

asnaseer
 3 years ago
Best ResponseYou've already chosen the best response.1np :) it just helps posting each question separately as others can then see each question more easily and also learn from them. :)
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.