Question

help me in solving this​

Answer 1

Put -ac = ab + bc ; -ab = ac+ bc and -bc =ab + ac

you get :

=(1/(a2+ab+ac))+(1/(c2+ac+bc))+(1/(a2+ab+ac))

=(1/a(a+b+c))+(1/b(a+b+c))+(1/c(a+b+c))

By taking LCM we get

=(ab + bc + ca)/[(a+b+c)(abc)]

put, ab+bc+ca=0

you get value = 0/[(a+b+c)(abc)] = 0