rajat Bansal
Last Activity: 9 Years ago
a2 +9b2+25c2= 15bc+5ac+3ab
a2 + 9b2 +25c2 -15bc-5ac-3ab=0
multyply by 2
2a2+18b2+50c2-30bc-10ac-6ab=0
a2-6ab +9b2 +9b2-30bc+25c2+ 25c2-10ac +a2=0
(a-3b)2 +(3b-5c)2 +(5c-a)2=0
square of any no is always positive and sum of three positive no can’t be zero so
a=3b,
3b=5c
5c=a
so basically
a=3b=5c
hence
b=a/3
c=a/5
so our nos are a,a/3,a/5
which are in H.P.
1/a +5/a =2*3/a