SOLUTION: (a+b+c+d)^2<=4(a^2+b^2+c^2+d^2)

Algebra ->  Inequalities -> SOLUTION: (a+b+c+d)^2<=4(a^2+b^2+c^2+d^2)      Log On


   

Question 743374: (a+b+c+d)^2<=4(a^2+b^2+c^2+d^2)
Found 2 solutions by Menjax, mathyguy:
Answer by Menjax(62) About Me  (Show Source):
You can put this solution on YOUR website!
What is the question?

Answer by mathyguy(1) About Me  (Show Source):
You can put this solution on YOUR website!
Omg, he is clearly asking you to prove it, duh. You are clearly not an Algebra master if you don't even know this simple identity, I think you are some kind of troller.
By the Cauchy-Schwarz Inequality we have:
(a+b+c+d)^2<=(1+1+1+1)(a^2+b^2+c^2+d^2)