Question -
Answer -
If a2, b2,c2 are in AP then, b2 – a2 = c2 –b2
If a/(b+c), b/(c+a),c/(a+b) are in AP then,
b/(c+a) – a/(b+c) =c/(a+b) – b/(c+a)
Let us take LCM onboth the sides we get,

Since, b2 –a2 = c2 – b2
Substituting b2 –a2= c2 – b2 in above, we get
LHS = RHS
Hence, given terms arein AP