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Question-173610




Question Number 173610 by AgniMath last updated on 14/Jul/22
Answered by okbruh123 last updated on 14/Jul/22
Method 1 :  as far as i know, this is problem of prmo.  its objective exam, so take any a,b,c following Σa=0  let′s say −3,+1,+2  youll get (9/2)+(1/(−6))+(4/(−3))=((27−1−8)/6)=3  Aliter :  if u wanna do legit,  ⇒(((b+c)^2 a+(a+c)^2 b+(a+b)^2 c)/(abc))  ⇒a+b+c=0 ⇒ b+c=−a and symmetrically you can solve for a+c anda+b  ⇒((a^3 +b^3 +c^3 )/(abc)) ⇒ (((a+b+c)_(=0) (a^2 +b^2 +c^2 −ab−bc−ca)+3abc)/(abc))  ⇒((3abc)/(abc))=3
Method1:asfarasiknow,thisisproblemofprmo.itsobjectiveexam,sotakeanya,b,cfollowingΣa=0letssay3,+1,+2youllget92+16+43=27186=3Aliter:ifuwannadolegit,(b+c)2a+(a+c)2b+(a+b)2cabca+b+c=0b+c=aandsymmetricallyyoucansolvefora+canda+ba3+b3+c3abc(a+b+c)=0(a2+b2+c2abbcca)+3abcabc3abcabc=3
Commented by Tawa11 last updated on 14/Jul/22
Great sir
Greatsir
Answered by behi834171 last updated on 14/Jul/22
a+b+c=0⇒Σa^3 =3abc  LH=Σ(((−a)^2 )/(bc))=Σ(a^2 /(bc))=((Σa^3 )/(abc))=((3abc)/(abc))=3 .■
a+b+c=0Σa3=3abcLH=Σ(a)2bc=Σa2bc=Σa3abc=3abcabc=3.◼

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