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Question Number 49604 by Tawa1 last updated on 08/Dec/18
Show that:           (((a + b)^2 )/2)  ≤  a^2  + b^2
Showthat:(a+b)22a2+b2
Answered by afachri last updated on 08/Dec/18
let                  (a − b)^2   ≥  0               a^2 − 2ab + b^2   ≥  0                             a^2  + b^2   ≥  2ab                a^2 + 2ab + b^2   ≥  2ab + 2ab                           (a + b)^2   ≥  4(ab)    meanwhile  :  ab  =  (( (a + b)^2  −  (a^2 + b^2 ) )/2)                 (a + b)^2   ≥   4((( (a + b)^2  − (a^2 + b^2 ))/2))                 (a + b)^(2 )  ≥  2(a + b)^2  − 2(a^2 + b^2 )]            −(a + b)^2   ≥  −2(a^2 + b^2 )                (((a + b)^2 )/2)  ≤  (a^2 + b^2 )
let(ab)20a22ab+b20a2+b22aba2+2ab+b22ab+2ab(a+b)24(ab)meanwhile:ab=(a+b)2(a2+b2)2(a+b)24((a+b)2(a2+b2)2)(a+b)22(a+b)22(a2+b2)](a+b)22(a2+b2)(a+b)22(a2+b2)
Commented by Tawa1 last updated on 08/Dec/18
God bless you sir.
Godblessyousir.
Commented by Tawa1 last updated on 08/Dec/18
Sir please help with this too    Show that:      ((abcd))^(1/4)    =  (1/4) (a + b + c + d)
SirpleasehelpwiththistooShowthat:abcd4=14(a+b+c+d)
Commented by afachri last updated on 08/Dec/18
  Arithmaric Mean =  ((a + b + c + d)/4)    Geometric Mean  =  ((abcd^ ))^(1/4)       Arithmatic Mean  ≥  Geometric Mean               (1/4)(a + b + c + d)  ≥  ((abcd^ ))^(1/4)      so, the equalty can be achieved only    and if only :                                      a = b= c = d    then                (1/4)(a + b + c + d)  =  ((abcd^ ))^(1/4)
ArithmaricMean=a+b+c+d4GeometricMean=abcd4ArithmaticMeanGeometricMean14(a+b+c+d)abcd4so,theequaltycanbeachievedonlyandifonly:a=b=c=dthen14(a+b+c+d)=abcd4
Commented by Tawa1 last updated on 08/Dec/18
God bless you sir
Godblessyousir
Commented by afachri last updated on 08/Dec/18
ur welcome, Sir.  Pardon me, are u an Indonesian ?
urwelcome,Sir.Pardonme,areuanIndonesian?
Commented by Tawa1 last updated on 08/Dec/18
No sir
Nosir
Commented by afachri last updated on 08/Dec/18
nevermind Sir.  i′m just asking Sir. :)
nevermindSir.imjustaskingSir.:)
Commented by Tawa1 last updated on 08/Dec/18
Ok sir
Oksir
Commented by Tawa1 last updated on 08/Dec/18
What if the first question is:      (((a+ b)/2))^2   ≤  ((a +b)/2)
Whatifthefirstquestionis:(a+b2)2a+b2
Commented by Tawa1 last updated on 08/Dec/18
How will the prove be
Howwilltheprovebe
Commented by afachri last updated on 08/Dec/18
  i had given the 2 solutuions earlier Sir.    what kind of proof else you sesrching    for Sir ?? i′m sorry i don′t get it.
ihadgiventhe2solutuionsearlierSir.whatkindofproofelseyousesrchingforSir??imsorryidontgetit.
Answered by afachri last updated on 08/Dec/18
according to  QM−AM  QM  ≥  AM               (√( (( a^2^   +  b^2   )/2)  ))≥  (( a + b )/( 2))   then square both sides.                        (( a^2  +  b^2   )/2)  ≥  (( (a + b)^2 )/( 4_ ))                             a^2 + b^2   ≥  (((a + b)^2 )/2)
accordingtoQMAMQMAMa2+b22a+b2thensquarebothsides.a2+b22(a+b)24a2+b2(a+b)22
Commented by Tawa1 last updated on 08/Dec/18
God bless you sir
Godblessyousir
Commented by Tawa1 last updated on 08/Dec/18
What is  QM and AM sir
WhatisQMandAMsir
Commented by afachri last updated on 08/Dec/18
you′re welcome,Sir
yourewelcome,Sir
Commented by Tawa1 last updated on 08/Dec/18
???
???
Commented by afachri last updated on 08/Dec/18
quadratic mean and  arithmaric mean
quadraticmeanandarithmaricmean
Commented by Tawa1 last updated on 08/Dec/18
God bless you sir. I really appreciate your time
Godblessyousir.Ireallyappreciateyourtime
Commented by afachri last updated on 08/Dec/18
it′s been my pleasure Sir
itsbeenmypleasureSir

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